Firefox – Right edge of the screen gets cut off when a dialog pops up

Support GNOME
1

No answers on Reddit, so here I go.

This is pretty much a fresh install. Happens both inside and outside of a virtual machine.

Only happens in Gnome as far as I can tell (i.e. doesn’t happen in Plasma)

1360×703 130 KB

$ inxi -fxxxrza

CPU:
  Info: Dual Core model: Intel Core i5-7200U bits: 64 type: MCP 
  arch: Amber/Kaby Lake note: check family: 6 model-id: 8E (142) stepping: 9 
  microcode: FFFFFFFF L2 cache: 3 MiB bogomips: 10853 
  Speed: 2712 MHz min/max: N/A Core speeds (MHz): 1: 2712 2: 2712 
  Flags: apic arch_capabilities clflush cmov constant_tsc cpuid cx8 de 
  flush_l1d fpu fsgsbase fxsr ht hypervisor invpcid invpcid_single lahf_lm 
  lm mca mce md_clear mmx msr mtrr nonstop_tsc nopl nx pae pat pcid pge pni 
  pse pse36 pti rdtscp rep_good sep sse sse2 sse4_1 sse4_2 ssse3 syscall tsc 
  tsc_known_freq vme xtopology 
  Vulnerabilities: Type: itlb_multihit status: KVM: VMX unsupported 
  Type: l1tf mitigation: PTE Inversion 
  Type: mds mitigation: Clear CPU buffers; SMT Host state unknown 
  Type: meltdown mitigation: PTI 
  Type: spec_store_bypass status: Vulnerable 
  Type: spectre_v1 
  mitigation: usercopy/swapgs barriers and __user pointer sanitization 
  Type: spectre_v2 
  mitigation: Full generic retpoline, STIBP: disabled, RSB filling 
  Type: srbds status: Not affected 
  Type: tsx_async_abort status: Not affected 
Repos:
  Packages: pacman: 1049 lib: 350 flatpak: 0 
  Active pacman repo servers in: /etc/pacman.d/mirrorlist 
  1: https://manjaro.mcofficer.me/stable/$repo/$arch
  2: https://uk.mirrors.fossho.st/manjaro/stable/$repo/$arch
  3: https://ct.mirror.garr.it/mirrors/manjaro/stable/$repo/$arch
2

Using gnome here, not seeing this, are you on wayland? (I’m not)

3

Disable all extensions, log off and log back in. Can you reproduce it? If not, enable extensions one by one to identify the culprit.

4

Probably, it’s a fresh install and Wayland is enabled by default. Let me check …
Actually no, I’m on X11. I think the OS detected I’m using a virtual machine

5

I can reproduce this in a freshly installed VM (20.2.1) when closing the browser with more then 1 tab open.
image

But not on my fully updated production machine. (using matcha-dark-sea theme)
Tried different themes, layouts, disabled all extentions, removed manjaro branding from the layouts settings menu, full update. no sign of something that triggers this.

6

Again, this is a fresh install. I’ll try what you’re suggesting, but if that was the case why does Manjaro include an extension causing this kind of issues?
Disabled every extension and then Extensions entirely, same issue.

7

Process of elimination. It’s common troubleshooting step for GNOME.

8

I’ve made a little progress, so far I can only force the grey bar to show when closing at fullscreen. (with normal defaults) I can ’ fix it’ using this instruction from FF and resetting everything.
https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

9

seems to be specific to running default Gnome in a VM - instead of on real hardware
I can can confirm this (running Manjaro Gnome in VirtualBox) - but I probably wouldn’t have even noticed without this heads up and the subsequent deliberate looking for it.

10

Thanks, I’ll try that even though I can’t see why it should work.
Anyways I don’t think it’s a grey bar, it’s more like you can see the desktop background (and the right edge of the default background is grey). I may be wrong of course … I should try changing the background and see if the bar changes accordingly.

seems to be specific to running default Gnome in a VM - instead of on real hardware
I can can confirm this (running Manjaro Gnome in VirtualBox) - but I probably wouldn’t have even noticed without this heads up and the subsequent deliberate looking for it.

Mhh, I’m pretty sure it also happens on real hardware but can’t install Manjaro right now.

11

Ok, it worked! Thank you.
What can we conclude from this?
is Manjaro changing some default settings of Firefox before packaging their ISOs, causing this to happen? (Not on purpose obviously) I’ve got lots of complaints about Manjaro’s defaults (both on Gnome and Plasma), guess I’m gonna add this to the list?

12

That there is something that changed somewhere that causes this, unknown precisely when and that it might be related to default settings for firefox. Since reproduction is not a fix and the fix is a workaround at best and the issue is minute, I guess this will be solved in future releases as a byproduct of the improvements in the release cycles.

Feedback is welcomed, but remember that a complaint is more of a supplier-buyer relationship, so I would phrase it as suggestions. Did you know you can build your own Manjaro with your own defaults?

13

I was a bit too hasty. Refreshing Firefox solves the issue momentarily: if you close the app without refreshing, then launch it again (and, of course, trigger some kind of dialogue to pop up), the right edge is still cut off.
So yeah, refreshing Firefox every time clearly isn’t an acceptable workaround (considering the issue at hand)

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