fix(ui): shifting no longer resets opacity of added tags

src/tagstudio/qt/controllers/tag_suggest_box.py

@@ -98,7 +98,26 @@ class TagSuggestBox(SuggestBox[Tag]):
         else:
             self._update_hint_icon()
 
-        return super()._on_shift_held(held)
+        # NOTE: This code is similar to the base method, but needs to reference the tag IDs for each
+        # widget and compare those against the self.added list.
+        for i in range(0, self.layout().content_layout.count()):
+            underlined_widget = self.layout().content_layout.itemAt(i).widget()
+            assert isinstance(underlined_widget, UnderlinedWidget)
+
+            if held and i == self._selection_index:
+                self._is_shift_held = True
+                opacity_effect = QGraphicsOpacityEffect(self)
+                opacity_effect.setOpacity(0.3)
+                underlined_widget.widget.setGraphicsEffect(opacity_effect)
+            else:
+                tag_widget = underlined_widget.widget
+                if not isinstance(tag_widget, TagWidget):
+                    return
+                if not tag_widget.tag:
+                    return
+                if tag_widget.tag.id not in self.added:
+                    self._is_shift_held = False
+                    underlined_widget.widget.setGraphicsEffect(None)  # pyright: ignore[reportArgumentType]
 
     @override
     def _update_hint_icon(self) -> None: