Affected Version: Gerrit Code Review (2.15.2-4606-g8edf152a17) 

What steps will reproduce the problem?
1. Open a CL and click 'Choose trybots'
2. Filter, e.g. type 'linux_' into the box.
3. Tick 'linux_chromium_rel_ng'.
4. Remove the filter, and examine the list of bots and which ones are ticked.

What is the expected output?

Only the 'linux_chromium_rel_ng' bot ticked is selected.

What do you see instead?

'linux_chromium_rel_ng' is selected, and also random other bots, usually 'cast_shell_linux' but sometimes others.

This isn't just 'linux_chromium_rel_ng' e.g. I just filtered for 'win_', selected 'win_chromium_x64_rel_ng' and I also ended up having 'android_clang_dbg_recipe' selected.

Not sure I can grok a pattern here, but /maybe/ the same row in the (hidden) unfiltered selection is being selected in the filtered selection.

What is the output of the JS console log (if applicable)?

Nothing new appears in JS console while performing the repro steps above.

Please provide any additional information below.