I have black border issues still under i3, lxde and xfce4.
I use no compositing and not even possible since I use my desktop remotely with X2Go 80% and only 205 locally when under i3 it is fairly the same.

uname -a:
Linux robert-aspire 6.7.7-1-MANJARO #1 SMP PREEMPT_DYNAMIC Fri Mar 1 18:26:06 UTC 2024 x86_64 GNU/Linux

screenfetch -N -n
kuszi@robert-aspire
OS: Manjaro 23.1.4 Vulcan
Kernel: x86_64 Linux 6.7.7-1-MANJARO
Uptime: 3d 23h 15m
Packages: 2140
Shell: bash
Resolution: 1920x1027
DE: Xfce4
WM: Xfwm4
WM Theme: Default
GTK Theme: Matcha-aliz [GTK2]
Icon Theme: elementary
Font: Source Sans Pro Light 12
Disk: 549G / 1,2T (49%)
CPU: Intel Core i3-10110U @ 4x 4.1GHz [66.0°C]
GPU: UHD Graphics
RAM: 2761MiB / 35789MiB

Use graphics acceleration when available: disabled in Opera

Also tested: opera --use-gl=desktop

Opera One(version: 109.0.5097.38)

Is there any other solution? I also read earlier threads back in 2017, 2020-2021 here