Rather than special-case chrome:// icons, I think we should tackle the larger issue that favicons don't look good on arbitrary background colors.  We didn't use to have this problem when we didn't use favicons in the dropdown, but now that we use them we do.

In the location bar itself we basically dealt with this by claiming that we could use the normal colors on light backgrounds, and should use white on dark backgrounds.  It would be nice to be consistent between these two places.  One way to do this would basically be, for all rows at all times, if the background is dark, show the icon in question in light-on-dark greyscale.  I assume we already have some Skia functionality somewhere that can do that.

Another way would be, we use full color icons on backgrounds that are "close to white or black" and use light or dark greyscale versions against backgrounds in between those two.

Also relevant here:  bug 740722  / https://chromium-review.googlesource.com/c/chromium/src/+/949449 .

re: 2
I don't think we should let "perfect" get in the way of better. We can improve for our own favicons (guaranteed to have only one color) without dealing with arbitrary favicons, which would be harder/impossible to colorize well. We already do this on the bookmark bar for incognito mode.

I don't mind shipping something that's incrementally better, especially if the code cost is small (supply a different color to the vector icon creation function when the background is dark).

I just think we should be thinking about the larger issue :)

Sure. It's my understanding that this will come up less often when we switch windows to using a grey highlight, like the other platforms.

We could also mock up what a lighter-color frame underneath the favicon would look like (white tinted by the selection color, say 80% white 20% selection color). I think we can expect all favicons to render OK on white or light colors.

We also need to solve this in Task Manager, but I believe whatever solution we end up with will cover both.

I floated the idea of having a different-color background by Alan and he didn't like it at first glance and I kinda agree it'll look wonky. The omnibox doesn't look affected by themes so the original issue (low contrast to chrome:// favicons) should at least be resolved.

I think it's preferable to move to the light-grey highlight since we know that we want that and we're not sure how or if we can handle the general case.

Omnibox dropdown is affected by system themes currently, and even in the default theme can be either light or dark.

I think more urgently we should address the default. Most favicons look like they'd be OK on either light or dark (which is what they are in incognito). I think the highlight blue is throwing favicons off their game.

I'll drop this as shrug since the omnibox dropdown colors are changing for Material refresh. Marking as WontFix feel free to reopen if you wanna take it.