Web composer improvements (#2257)

* Keep the emoji picker in the tablet width (close #1880)

* Support pressing tab to select a mention (close #1831)

src/view/com/composer/Composer.tsx

@@ -452,7 +452,7 @@ export const ComposePost = observer(function ComposePost({
               <OpenCameraBtn gallery={gallery} />
             </>
           ) : null}
-          {isDesktop ? <EmojiPickerButton /> : null}
+          {!isMobile ? <EmojiPickerButton /> : null}
           <View style={s.flex1} />
           <SelectLangBtn />
           <CharProgress count={graphemeLength} />

src/view/com/composer/text-input/web/Autocomplete.tsx

@@ -134,7 +134,7 @@ const MentionList = forwardRef<MentionListRef, SuggestionProps>(
           return true
         }
 
-        if (event.key === 'Enter') {
+        if (event.key === 'Enter' || event.key === 'Tab') {
           enterHandler()
           return true
         }