In bug 1941426 we opted to only support icons in the element that wraps the select, and not in the options themselves. Our reasoning was that native support for customizable selects/options is forthcoming in bug 1944403 and the related work, and we didn't want to reinvent the wheel only to have to un-do a bunch of work down the line.

We may need to go back to the drawing board as having the ability to show icons in select options is now blocking bug 1972068. The simplest option is likely to take the select-like element that was created using panel-list for the import wizard and re-purpose it/make it reusable for the search case.

mstrimer on slack: I wonder if we can catch a click on the select and open that special panel list if there are icons in the moz-options. Might not be too much work. Using the new command interface API or something may simplify things a little too

https://developer.mozilla.org/en-US/docs/Web/API/Invoker_Commands_API

bonus points for setting width to anchor size + using anchor positioning: https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Anchor_positioning

https://hg.mozilla.org/mozilla-central/rev/057e70e6e755