Steps to reproduce:

• Goto https://www.tucan.tu-darmstadt.de/
• Click in to the TU-ID or Passwort field

What you get:
There is huge blue border only on the left side. It looks very weird and distracting.

What I expected:
In the native GTK theme there is only like one pixel of black on the left side. I had literally not seen it before Emilio pointed it out to me. I think in combination with the cursor appearing at the same time it's almost not noticeable.
Chrome seems to have a smallish border around the whole input.

Personal aside: I think the current focus outline should not be shipped. It's simply too much. Chrome on Linux has like maybe 2px. GTK was even less for me.

I don't see focus outline for the TU-ID or Passwort fields whatsoever with widget.disable-native-theme-for-content on Windows. Is there a Linux-specific code path?

Tracking for Fission M7 Beta.

I can reproduce this bug in a clean profile. Here's a screenshot from macOS. (I wasn't able to reproduce on Windows earlier due to some profile problem I haven't diagnosed yet.)

I just filed bug 1690194 about the dark blue focus ring being much darker than what was spec'd, but that might be a duplicate of this bug now that I've seen it.

So... bug 1689615 makes it just one ring, which should improve this significantly.

I think that's fine. We could make it a 1px ring if needed, and paint it over the border, which would match chrome, but that seems unfortunate to me because it doesn't behave like a regular outline anymore.

Please reopen if you disagree or think it's still too much after the change in bug 1689615.