I've encountered several issues with Opera GX after the recent update 115.0.5322.142:
O Menu: The O menu takes up too much space, hiding the "Exit button" below "Update and Recovery button".
Bookmarking: when bookmarking webpage, The Bookmark popup UI takes a long time to load and glitches. When it finally loads, it displays a half-moon icon glitch and doesn't load properly.
Thumbnails: Bookmark thumbnails now appear as title strips rather than proper thumbnails.
The overall user experience has deteriorated significantly. For context, I'm using a 15.5-inch laptop with an i3 processor, 8GB RAM, and a 500GB SSD.