diff --git a/.eslintrc.js b/.eslintrc.js
index 87c8e21b232..fc548f0c1db 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -14,6 +14,9 @@ module.exports = {
 		'comma-dangle': 'off',
 		'jsdoc/no-defaults': 'off',
 		'@typescript-eslint/no-unused-vars': 'off',
+		// Forbid import without extension even when TS is used
+		// TODO: fix in @nextcloud/eslint-config/typescript
+		'import/extensions': 'error',
 		'import/newline-after-import': 'warn',
 		'import/no-named-as-default-member': 'off',
 		'import/order': [
diff --git a/src/components/AvatarWrapper/AvatarWrapper.vue b/src/components/AvatarWrapper/AvatarWrapper.vue
index af592583672..89be73c3739 100644
--- a/src/components/AvatarWrapper/AvatarWrapper.vue
+++ b/src/components/AvatarWrapper/AvatarWrapper.vue
@@ -55,7 +55,7 @@ import NcAvatar from '@nextcloud/vue/dist/Components/NcAvatar.js'
 
 import { ATTENDEE, AVATAR } from '../../constants.js'
 import { getUserProxyAvatarOcsUrl } from '../../services/avatarService.ts'
-import { isDarkTheme } from '../../utils/isDarkTheme'
+import { isDarkTheme } from '../../utils/isDarkTheme.js'
 
 export default {
 
diff --git a/src/components/RightSidebar/Participants/ParticipantsSearchResults/ParticipantsSearchResults.vue b/src/components/RightSidebar/Participants/ParticipantsSearchResults/ParticipantsSearchResults.vue
index 4f6d1cd3b5b..2d557575002 100644
--- a/src/components/RightSidebar/Participants/ParticipantsSearchResults/ParticipantsSearchResults.vue
+++ b/src/components/RightSidebar/Participants/ParticipantsSearchResults/ParticipantsSearchResults.vue
@@ -104,7 +104,7 @@ import NcEmptyContent from '@nextcloud/vue/dist/Components/NcEmptyContent.js'
 import Hint from '../../../Hint.vue'
 import ParticipantsList from '../ParticipantsList/ParticipantsList.vue'
 
-import { ATTENDEE } from '../../../../constants'
+import { ATTENDEE } from '../../../../constants.js'
 import { useIntegrationsStore } from '../../../../stores/integrations.js'
 
 const isCirclesEnabled = loadState('spreed', 'circles_enabled')
diff --git a/src/components/RightSidebar/Participants/ParticipantsTab.vue b/src/components/RightSidebar/Participants/ParticipantsTab.vue
index e543a1eef62..1927ad6c6f1 100644
--- a/src/components/RightSidebar/Participants/ParticipantsTab.vue
+++ b/src/components/RightSidebar/Participants/ParticipantsTab.vue
@@ -85,7 +85,7 @@ import SelectPhoneNumber from '../../SelectPhoneNumber.vue'
 import { useGetParticipants } from '../../../composables/useGetParticipants.js'
 import { useIsInCall } from '../../../composables/useIsInCall.js'
 import { useSortParticipants } from '../../../composables/useSortParticipants.js'
-import { ATTENDEE } from '../../../constants'
+import { ATTENDEE } from '../../../constants.js'
 import { searchPossibleConversations } from '../../../services/conversationsService.js'
 import { EventBus } from '../../../services/EventBus.js'
 import { addParticipant } from '../../../services/participantsService.js'