[MS] File viewers minor improvements

- fix the viewer wrapper height on firefox
- reset the zoom level when the text viewer is mounted

client/src/views/viewers/FileViewer.vue

@@ -313,7 +313,6 @@ async function onClick(event: MouseEvent): Promise<void> {
 .container {
   height: 100%;
   height: -webkit-fill-available;
-  height: -moz-available;
   height: stretch;
   margin: 0 1em 1em 1em;
   padding: 1.5em;

client/src/views/viewers/FileViewerWrapper.vue

@@ -44,7 +44,6 @@ defineProps<{
 .file-viewer-wrapper {
   height: 100%;
   height: -webkit-fill-available;
-  height: -moz-available;
   height: stretch;
   display: flex;
   justify-content: center;

client/src/views/viewers/TextViewer.vue

@@ -36,6 +36,7 @@ const zoomControl = ref();
 const zoomLevel = ref(1);
 
 onMounted(async () => {
+  zoomLevel.value = 1;
   const text = new TextDecoder().decode(props.contentInfo.data);
   editor.value = monaco.editor.create(container.value, {
     value: text,

newsfragments/8854.feature.rst

@@ -0,0 +1 @@
+Add file viewers for some common file types (audio, image, pdf & docx)