FancyZones causing issues when used with Firefox (the browser window decreases in size until it's just a small line when scrolling/moving mouse)

[PyHatTech]

Microsoft PowerToys version

0.86.0

Installation method

GitHub

Running as admin

Yes

Area(s) with issue?

FancyZones

Steps to reproduce

I'm using the latest version of Firefox (133.0 64-bit). Have created zones with fancyzones and it was working fine, but recently a strange issue is now consistently happening. When I pin a Firefox window in one of the zones, the right side of the window moves to the left and the bottom side moves up until there is basically nothing left. It looks like it's getting smaller on it's own, but it's actually any interaction you have with the window (scrolling, clicking etc.). It keeps getting smaller until it's basically gone. While it's getting smaller, I can move the window, maximize it by moving it to the top of the screen, but it just keeps getting smaller again. The window is basically rendered useless when the issue starts.

✔️ Expected Behavior

Fixefox window should just pin in the selected fancyzone and not get smaller when I'm scrolling/clicking inside the window.

❌ Actual Behavior

This isn't happening to any other application I'm using, including Chrome and Windows Explorer. This is also not happening when I use the built-in zone feature (hover on maximize button in a window and select a zone). It's only happening when using fancyzones. Sometimes it doesn't happen after pinning a window in a zone. When I do it multiple times, it does happen. The chance of it happening is about 30% based on my testing. It also doesn't matter which zone I'm using. When I move a Firefox tab outside of the window (creating a second/separate window), the new browser window is fine... until I snap it to a fancyzone.

Have searched quite a bit and can't find anything online where people are experiencing this and I don't think it's something I'm supposed to share as a bug with the Firefox developers. Important to note, the window isn't "resizing" as I can see that the minimize/maximize/close buttons are not moving to fit in the window. When the window gets smaller, the entire interface including the content is simply being cut off. Have closed all other applications to make sure something else isn't influencing this.

Other Software

No response

[similar-issues-ai]

We've found some similar issues:

• Fancy Zones #18267 , similarity score: 81%

If any of the above are duplicates, please consider closing this issue out and adding additional context in the original issue.

Note: You can give me feedback by 👍 or 👎 this comment.

[PyHatTech]

if anyone has suggestions on a setting in Firefox that could prevent this issue from happening, please let me know.

[Leo-skr]

I've been experiencing the problem you describe for a couple of days now as well, and unfortunately I haven't found a solution either. Perhaps it would be wise to open a support ticket with Mozilla, as I have only had this problem with Firefox, which may indicate that it is a Firefox issue and not a Fancy Zone issue.

[PyHatTech]

@Leo-skr thanks for the comment. Good to hear that I'm not the only one. It's such a strange issue that it made me think for a second I was hacked and someone was messing with me :D. PowerToys is kind of a niche/IT-pro application which makes me doubt that this is an issue that the Mozilla team will investigate/fix, but I will consider reporting it to them as well. Have uninstalled PowerToys for now and started using the built-in feature in Windows. I'm only using fancyzones and the layout I have is one of the built-in options in Windows. Not having the option to use "shift" to drop a window in one of the zones is annoying (have shift & ctrl always mapped on my mice), so I'll probably want to use PowerToys again.

[Leo-skr]

Funny, I also have shift & ctrl mapped to my mice haha. As I use the PowerToys FancyZones a lot, I don't plan on turning it off, as a quick Firefox restart temporarily fixes the problem for me, and it only happens once in a few tries. I'll keep you updated if anything changes or if I find a fix.

[CDeLeon94]

Reproduction Notes:

• it seems to happen only on windows with more than 1 tab
• I think only after using middle click to enable spanning the window across multiple zones
• The shrinking issue, while seemingly triggered by fancyzones, once triggered, the effected window continues to shrink after fancyzones has been closed.

[CDeLeon94]

Oh, and Firefox 133 Release Notes (Used by OP and I) mention

Canvas2D switched from Direct2D to a platform independent acceleration backend on Windows.

Which sounds like it could be relevant

Edit: I was on Powertoys 83 (I believe) when I had the issue, but none of the windows have started doing this since updating to 86.

[Leo-skr]

@CDeLeon94

Regarding your reproduction notes:

• For me it doesn't matter how many tabs are open in the Firefox instance dragged into a fancyzone.
• The issue sometimes happens when dragging a Firefox instance with Shift, the easiest way for me to reproduce it is to drag a Firefox instance and press Shift repeatedly until the issue occurs.

Finally, regarding the new Powertoys, version 0.86 did not prevent the described problem.

[CDeLeon94]

@Leo-skr Ah, with that shift key note I was able to easy trigger it again, even on the single tab - private window that I was previously unable to reproduce (in my admittedly brief testing)

[Leo-skr]

@CDeLeon94 No worries :) It's generally also a really weird bug

[PyHatTech]

@CDeLeon94 @Leo-skr recommend checking the box for "Use recommended performance settings" in Firefox settings. Believe this is hardware acceleration and you can find the setting by searching for "hardware". Have checked/unchecked that setting many times before to fix weird issues I was experiencing with YouTube and it didn't help, so I was kind of pessimistic that it would help now.

The issue happened once when I was installing the latest Nvidia studio driver, but now as I keep trying to reproduce it... it's not happening. My guess is that it's a combination of Nvidia, PowerToys and Firefox software, which probably makes it more difficult to address. Also regarding mapping shift + ctrl to the mouse: recommend checking "x-mouse". When I hold shift and use the scroll wheel of my mouse, that allows me to control system volume. Also using it for switching to the virtual desktop left right (hold ctrl and use left/right mouse click). It's quite easy to set up and really adds to the fancyzones experience imo.

[Leo-skr]

@CDeLeon94 @PyHatTech
Thanks for the tip!

Checking "Use recommended performance settings" actually solved the issue for me, as far as I can tell. I don't use NVIDIA Studio drivers so I can't comment on that.

I'll definitely check out x-mouse too, thanks for the suggestion!

[CDeLeon94]

@PyHatTech re-enabling hardware acceleration and restarting firefox seems to have resolved the issue for me.

I'm guessing I had disabled hardware acceleration at some point trying to diagnose some GPU stuttering issues I was having a while back.