Steps to replicate the issue (include links if applicable):

• Open any item in Firefox (I'm on Firefox version 124.0 (64-bit) on Ubuntu FWIW). I will use https://www.wikidata.org/wiki/Q73620655 as an example. You can do this when not logged in
• Click "Add statement"
• Add a new property "language of work or name"
• Use up/down buttons to select "Chinese"

What happens?:

• When highlighting any of the suggestions, the item selector searches for that suggestion and gives new suggestions based on the label of the highlighted item

What should have happened instead?:

• The list should remain pretty static (except for loading new suggestions at the bottom, of course)

Software version (skip for WMF-hosted wikis like Wikipedia):

Other information (browser name/version, screenshots, etc.):
Happens both when I'm logged in and logged out, but only in Firefox, not in Chrome.