Comment 0 for bug 1765304

tl;dr: starting in Ubuntu 18.04, "ibus" seems to lower and raise Firefox, whenever the user tries to focus an <input type="password"> field on a web page. This is not a regression in Firefox, as the same Firefox version runs just fine in Ubuntu 17.10 -- it seems to be a bug in ibus, because it only happens (in 18.04) when the environmental variable GTK_IM_MODULE is at its default value (which is "ibus"). It had this same value in 17.10 but the bug didn't happen there; hence, I'm guessing there was a change in ibus (or a related package) that caused this breakage / lowering+raising.

This is pretty bad, because in some cases, the focus-loss can mean users are simply unable to fill in password fields that previously were working fine. (see "ACTUAL RESULTS" below)

STEPS TO REPRODUCE #1, via "BitWarden" Firefox extension:
=========================================================
 1. Start Firefox. (fresh profile if you like)
 2. Install BitWarden from https://addons.mozilla.org/en-US/firefox/addon/bitwarden-password-manager/
 3. Click the BitWarden toolbar icon to spawn a menu-pane.
 4. Click "Log in" at the bottom of that pane.
 5. Click the "Master Password" field.

ACTUAL RESULTS:
 The menu pane disappears as soon as the Master Password field receives focus.
EXPECTED RESULTS:
 I should be able to type in a password; pane shouldn't disappear.

STEPS TO REPRODUCE #2, via Reddit:
=================================
 1. Visit https://www.reddit.com/r/firefox/ (or any reddit page)
 2. Click "Log in or sign up in seconds" at the extreme upper right of the page.
      (click the "Log in" part of that sentence)
 3. Try to click the password field (or "tab" into it) and type in some text.

ACTUAL RESULTS:
 Try as you might, the password field never receives focus.
EXPECTED RESULTS:
 Password field should accept focus & let me type text into it.

If I run firefox from the command line with env var GTK_IM_MODULE="", then I get "expected results". But with the default value of that env var, I get "actual results" (broken behavior, unable to enter passwords).

I initially reported this in Firefox, here: https://bugzilla.mozilla.org/show_bug.cgi?id=1451466 (with a few dependent bugs for the usage-specific STR quoted above). But I think it's a bug in ibus, hence filing here now.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ibus 1.5.17-3ubuntu3
ProcVersionSignature: Ubuntu 4.15.0-15.16-generic 4.15.15
Uname: Linux 4.15.0-15-generic x86_64
ApportVersion: 2.20.9-0ubuntu5
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Wed Apr 18 23:22:05 2018
InstallationDate: Installed on 2018-04-17 (1 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Alpha amd64 (20180416)
SourcePackage: ibus
UpgradeStatus: No upgrade log present (probably fresh install)