Not able to resize Firefox (when sized via KWin)?

Hiya,

I'm using Firefox Flatpak, but am not able to resize Firefox, only when its been sized into a set proportion via KWin (tiling manager). As soon as I move the Firefox out of the set "zone" I can freely resize FF again. Anyone know whats going on here? I am always using multiple windows of Firefox open, and moving them around on multiple monitors, so for me this is rather important. This is on Bazzite.

Thanks for any suggestions

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