@mib2berlin
(this is the second time I'm typing this as Vivaldi pulled the whole system in an unresponsive "freeze" (first Vivaldi, then the explorer, the rest))
Lazy load is on, always has been. I've been noticing slowdowns ever since I opened a third Vivaldi window. First with Tab Suspender still on I noticed that the PC coming out of sleep mode wasn't immediately ready to go. Now without Tab Suspender, well I already mentioned the whole system becoming unresponsive. Before that pages not really loading or taking minutes to do so. Lots of weird behavior. Maybe Vivaldi isn't all that good at handling multiple windows especially when one or more are filled with a great many tabs?
I just had to do a hard reset (button) to get things working again. I noticed the edge of the screen turning red. That was part of this LG app for controlling your screen. The only new thing I installed recently so just in case I removed that (don't really need it, those settings can also be accessed though the screen itself).
Guess I'll have to see how things'll go for a wile.