Issue Summary

This is reproducible on Data Center: yes

Steps to Reproduce

1. (Prereq.) Having a large no. of user groups on the instance. For UI selector element glitch, 50 groups is enough
2. Enter the Filter subscription page, via Issue nav -> (any saved) filter -> Details link to display an inline dialog. Within it, click "New subscription".
3. Click Recipients drop-down selector and scroll through it

Expected Results

• a better select component with autocompletion/search and lazy-loading of data

Actual Results

• native select with all options loaded at once
• not user-friendly to navigate through potentially huge list
• can freeze the browser (lots of data to parse & render at once)

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available