Collections dialog is slow to open with many books selected
Steps to recreate:
- Add 100+ books to Gnome Books (may work with fewer)
- Right-click and then select all books
- Click "Collections" button
Expected behaviour:
- Gnome Books opens the Collections dialog quite quickly
Actual behaviour:
- Gnome Books doesn't indicate that it is loading
- App is generally unresponsive for several minutes (but not obviously using much CPU, or appearing near the top of "top")
- Pressing "Cancel" seems to do nothing
- Pressing Esc twice cancels the selection and the dialog