Affected versions

• latest Nightly 86.0a1
• latest Beta 85.0b3
• 84.0RC3

Affected platforms

• macOS 10.14.6

Prerequisites

• Have a second display connected to mac.

Steps to reproduce

1. Launch Firefox.
2. Go to http://jsbin.testim.io/soviruvalo/edit?html,output.
3. Click on the username field, and write some random strings inside it.
4. Click on the password field, and write some random strings inside it.

Expected result

• The dropdown menus are correctly displayed for each filed.

Actual result

• Blank spaces are left inside the dropdown menus.

Suggested Severity

• S3, since it's only specific to macOS 10.14.6, and it only happens while a second display is connected.

Regression range

• It looks to be an old regression, the issue doesn't reproduce on FF 72.0 (20200103162918). I will investigate more on this, in order to find a regression range.

Additional notes

• I was not able to reproduce this bug, if the second display is disconnect from my mac (I use a Lenovo 2k as a secondary display).

Last good revision: a0c804993efc599a95e97bea39fa1528fd0195d8 (2018-04-18)
First bad revision: 5d73549d363f2a52854ff43fabac9c6fd05b90b0 (2018-04-19)

Pushlog:
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=a0c804993efc599a95e97bea39fa1528fd0195d8&tochange=5d73549d363f2a52854ff43fabac9c6fd05b90b0

Looking at the pushlog, maybe Bug 1455151 has somehow regressed this, I'm not sure though. Unfortunately, I can't bisect further the range, due to this error, that appear to me on the mozregression terminal: "There are no build artifacts for these changesets (they are probably too old)." I hope this helps.

Bug 1454081 looks like a more likely regression candidate. Eitan, can you take a look at this?

I can reproduce this using Credit Card autofill as well by having a secondary monitor connected to my MacBook Pro. Moving this over to autofill component as it is not Password Manager specific.
If I disconnect my secondary monitor, this issue is no longer reproducible.

Hi Dimi,
Please take this issue into consideration too for the upcoming Credit Card Autofill work. It is a very easily reproducible issue and severely user-facing for macOS users with a 2nd monitor connected. Marking it S2 due to this, but feel free to lower severity if need be. Thanks!

Hi Timea,
Thanks for the information. I would like to confirm that does this bug only happen in macOS 10.14.6, or does this also happen in the other versions?
This might help us determine the priority, thanks!

Thanks for looking into it Dimi! My apologies for not mentioning that earlier, this issue was also reproduced on:

• MacOS Big Sur 11.1
• MacOS 10.15.7
  Seems like it is an issue affecting the latest macOS versions for laptops connected to a secondary monitor.

Also encountered it randomly in the dropdown from the Save Password doorhanger.

Not entirely sure if this is an autocomplete menu bug or layout bug or something else with MacOS, will investigate and report back. Probably has something to due with how the autocomplete popup and items set their own width via getBoundingClientRect() https://searchfox.org/mozilla-central/search?q=getBounding&path=autocomplete&case=false&regexp=false

Hmm, I'm not able to reproduce with either passwords or credit cards on Intel macOS Big Sur 11.6 on Nightly 94.0b5. I'm connected via USB-C to a 2K monitor and can't get the resizing issue to appear on either my external or laptop monitor. Maybe something fixed this in the meantime?

:timea, can you still reproduce this issue? If so, can you also specify if this issue happens on both monitors or just a specific monitor when an external one is plugged in. I don't think the way the external monitor is connected really matters, but might be good information to have as well (HDMI vs display port vs USB-C). Thanks!

Hey Tim,
I couldn't reproduce this issue either so far on the latest Nightly 95.0a1 nor the latest Beta 94.0b4 (64-bit) on a MacOS 10.15 device connected to an external 2k monitor via USB-C. I had a similar setup when I encountered this issue but with a different 2k monitor tho. Anyway, I didn't see this issue for some time but I'll needinfo? Cipri to check it out on his device as well so we get another confirmation.

Hey Cipri, please check this out as well when you have the time and let us know if you can still reproduce or not. This issue was somewhat intermittent for me back then and it would be nice to have another check on this.

I can't reproduce the bug either with macOS 10.14.6 on latest Nightly 95.0a1 and Beta 94.0b5.

I'm going to go ahead and close this as WORKSFORME, I wonder if we'll see this issue again or not. It'd be nice to get the bug that fixed this, but I'm not too concerned about that.