Thanks for looking into this.
After step 6 (above) I also did:
Step 7) Reload the jqwidget demo-page (using CTRL-R)
Step 8) Test #3 : again you get the same fault (the combobox is not reacting to keyboard input.
I also tested Firefox-87.0 (on Fedora Linux) and found the same faults.
I also tested Firefox-88.1 (on Windows 10) and here I could not reproduce the faults.
Regards,
Michiel
