diff --git a/polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip_html.js b/polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip_html.ts
similarity index 97%
rename from polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip_html.js
rename to polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip_html.ts
index 7c75488..f77b8cc 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_html.js b/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_html.ts
similarity index 94%
rename from polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_html.js
rename to polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_html.ts
index afd427a..c6c2b7f 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_html.js b/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_html.ts
similarity index 97%
rename from polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_html.js
rename to polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_html.ts
index c090416..c26e304 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_html.js b/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_html.js
rename to polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_html.ts
index 44afb84..dfcef4e 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_html.js b/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_html.js
rename to polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_html.ts
index 6fee9f3..2824bb5 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-alert/gr-alert_html.js b/polygerrit-ui/app/elements/shared/gr-alert/gr-alert_html.ts
similarity index 97%
rename from polygerrit-ui/app/elements/shared/gr-alert/gr-alert_html.js
rename to polygerrit-ui/app/elements/shared/gr-alert/gr-alert_html.ts
index e9f386d..d2aed40 100644
--- a/polygerrit-ui/app/elements/shared/gr-alert/gr-alert_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-alert/gr-alert_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_html.js b/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_html.ts
similarity index 97%
rename from polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_html.js
rename to polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_html.ts
index fecaa73..d3d2481 100644
--- a/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_html.js b/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_html.ts
similarity index 97%
rename from polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_html.js
rename to polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_html.ts
index c0e8abf..8ab4828 100644
--- a/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_html.js b/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_html.ts
similarity index 93%
rename from polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_html.js
rename to polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_html.ts
index cc8a42f..0d8e78f 100644
--- a/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-button/gr-button_html.js b/polygerrit-ui/app/elements/shared/gr-button/gr-button_html.ts
similarity index 98%
rename from polygerrit-ui/app/elements/shared/gr-button/gr-button_html.js
rename to polygerrit-ui/app/elements/shared/gr-button/gr-button_html.ts
index e992ffc..b272951 100644
--- a/polygerrit-ui/app/elements/shared/gr-button/gr-button_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-button/gr-button_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_html.js b/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_html.ts
similarity index 95%
rename from polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_html.js
rename to polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_html.ts
index 3b7b1af..c7930c0 100644
--- a/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_html.js b/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_html.js
rename to polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_html.ts
index 38e620f..542d8be 100644
--- a/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.js b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.ts
similarity index 98%
rename from polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.js
rename to polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.ts
index 837a58f..4c15383 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-comment/gr-comment_html.js b/polygerrit-ui/app/elements/shared/gr-comment/gr-comment_html.ts
similarity index 99%
rename from polygerrit-ui/app/elements/shared/gr-comment/gr-comment_html.js
rename to polygerrit-ui/app/elements/shared/gr-comment/gr-comment_html.ts
index 47ac8a6..a9d2491 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment/gr-comment_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-comment/gr-comment_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog_html.js b/polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog_html.js
rename to polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog_html.ts
index 2d0fa6f..6876c1a 100644
--- a/polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_html.js b/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_html.js
rename to polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_html.ts
index 9fc83c8..197c94c 100644
--- a/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_html.js b/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_html.ts
similarity index 91%
rename from polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_html.js
rename to polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_html.ts
index 3ed33d1..1489006 100644
--- a/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_html.ts
@@ -14,6 +14,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html``;
diff --git a/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_html.js b/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_html.ts
similarity index 93%
rename from polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_html.js
rename to polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_html.ts
index 2571065..a5dd6d0 100644
--- a/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_html.js b/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_html.js
rename to polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_html.ts
index 54b404d..f8ddcfd 100644
--- a/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_html.js b/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_html.ts
similarity index 98%
rename from polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_html.js
rename to polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_html.ts
index 3ea40d9..f9d971d 100644
--- a/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_html.js b/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_html.js
rename to polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_html.ts
index 7248e65..3bf0e87 100644
--- a/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_html.js b/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_html.ts
similarity index 98%
rename from polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_html.js
rename to polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_html.ts
index 0f80af2..629b0ad 100644
--- a/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_html.js b/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_html.ts
similarity index 98%
rename from polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_html.js
rename to polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_html.ts
index 6617a0e..8ea0d21 100644
--- a/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_html.js b/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_html.js
rename to polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_html.ts
index 24eb0b0..81a2c2f 100644
--- a/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_html.js b/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_html.ts
similarity index 97%
rename from polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_html.js
rename to polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_html.ts
index a226e30..5e36166 100644
--- a/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_html.js b/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_html.ts
similarity index 95%
rename from polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_html.js
rename to polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_html.ts
index 61e8b24..ce475c6 100644
--- a/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_html.js b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_html.js
rename to polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_html.ts
index 5cb8670..468bbee 100644
--- a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-hovercard-account/gr-hovercard-account_html.js b/polygerrit-ui/app/elements/shared/gr-hovercard-account/gr-hovercard-account_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-hovercard-account/gr-hovercard-account_html.js
rename to polygerrit-ui/app/elements/shared/gr-hovercard-account/gr-hovercard-account_html.ts
index 262b089..18138c3 100644
--- a/polygerrit-ui/app/elements/shared/gr-hovercard-account/gr-hovercard-account_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-hovercard-account/gr-hovercard-account_html.ts
@@ -14,8 +14,8 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import '../gr-hovercard/gr-hovercard-shared-style.js';
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import '../gr-hovercard/gr-hovercard-shared-style';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="gr-hovercard-shared-style">
diff --git a/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard-shared-style.js b/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard-shared-style.ts
similarity index 87%
rename from polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard-shared-style.js
rename to polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard-shared-style.ts
index 5fb1add..aa17acaf 100644
--- a/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard-shared-style.js
+++ b/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard-shared-style.ts
@@ -15,6 +15,11 @@
  * limitations under the License.
  */
 
+// Mark the file as a module. Otherwise typescript assumes this is a script
+// and $_documentContainer is a global variable.
+// See: https://www.typescriptlang.org/docs/handbook/modules.html
+export {};
+
 /** The shared styles for all hover cards. */
 const GrHoverCardSharedStyle = document.createElement('dom-module');
 GrHoverCardSharedStyle.innerHTML =
diff --git a/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_html.js b/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_html.ts
similarity index 92%
rename from polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_html.js
rename to polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_html.ts
index 67a3545..830cbd878 100644
--- a/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="gr-hovercard-shared-style">
diff --git a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_html.js b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_html.ts
similarity index 97%
rename from polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_html.js
rename to polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_html.ts
index 1722d02..dbc3b5e 100644
--- a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="gr-voting-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-label/gr-label_html.js b/polygerrit-ui/app/elements/shared/gr-label/gr-label_html.ts
similarity index 91%
rename from polygerrit-ui/app/elements/shared/gr-label/gr-label_html.js
rename to polygerrit-ui/app/elements/shared/gr-label/gr-label_html.ts
index c4310fc..94196df 100644
--- a/polygerrit-ui/app/elements/shared/gr-label/gr-label_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-label/gr-label_html.ts
@@ -14,6 +14,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html` <slot></slot> `;
diff --git a/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_html.js b/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_html.js
rename to polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_html.ts
index 615a525..fa50624 100644
--- a/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_html.js b/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_html.ts
similarity index 91%
rename from polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_html.js
rename to polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_html.ts
index 204aa87..f34f99e 100644
--- a/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <gr-js-api-interface id="jsAPI"></gr-js-api-interface>
diff --git a/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_html.js b/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_html.ts
similarity index 91%
rename from polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_html.js
rename to polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_html.ts
index 6bcce8c..b942d07 100644
--- a/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_html.ts
@@ -14,6 +14,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html` [[_computeDisplayText(text, limit)]] `;
diff --git a/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_html.js b/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_html.js
rename to polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_html.ts
index f1f5f46..a335db7 100644
--- a/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_html.js b/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_html.ts
similarity index 94%
rename from polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_html.js
rename to polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_html.ts
index 59bed1e..4bdc1ab 100644
--- a/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_html.js b/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_html.ts
similarity index 97%
rename from polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_html.js
rename to polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_html.ts
index ff73d4d8..75ee667 100644
--- a/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_html.js b/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_html.ts
similarity index 94%
rename from polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_html.js
rename to polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_html.ts
index 7123adb..730eeac 100644
--- a/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_html.js b/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_html.ts
similarity index 94%
rename from polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_html.js
rename to polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_html.ts
index c5e9142..facc4f8 100644
--- a/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_html.js b/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_html.ts
similarity index 95%
rename from polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_html.js
rename to polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_html.ts
index 0ce885a..934b3cb 100644
--- a/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_html.js b/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_html.js
rename to polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_html.ts
index 4a4480e..ef76999 100644
--- a/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_html.js b/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_html.ts
similarity index 97%
rename from polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_html.js
rename to polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_html.ts
index 8454f62..1f777aa 100644
--- a/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">
diff --git a/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_html.js b/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_html.ts
similarity index 93%
rename from polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_html.js
rename to polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_html.ts
index e5a2813..952420d 100644
--- a/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style>
diff --git a/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_html.js b/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_html.ts
similarity index 96%
rename from polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_html.js
rename to polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_html.ts
index 3f02fc5..d59a6c3 100644
--- a/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_html.ts
@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag';
 
 export const htmlTemplate = html`
   <style include="shared-styles">