I sometimes select click and rag over text and it can take up to 2 seconds for the highlight color to show up and it can take even slightly longer for the text formatting pop-up to show itself.
Here is an example that is not as extreme, this was just now. But you can see how unresponsive it is especially when I triple click to select a paragraph.
You can see how long it takes after I move my mouse from the paragraph I selected until it actually gets selected. And CPU and Memory just to prove that it’s not my PC that’s the problem.
This can sometimes get confusing and frustrating.