Well, I thought I'd been lucky, able to avoid the degraded performance problem people have been reporting. But alas, I got struck too.
Today suddenly L4 4.0c has started grinding to a halt when I try to switch tabs to one particular resource, a commentary: Exodus 19-40 (AYBC).
Also, when I reopen Logos with that tab as the active one, it's exceedingly slow. I can see the orange visual cues circles show up to direct my attention to the active verse, but they stay up on the screen for several seconds.
In one timing of this, it took 30 seconds from clicking on the tab until it came up on top and Logos woke up from its stupor. Other times it took 15 or 20 seconds.
Here are a couple of logs of two different times trying this. Nothing else remarkable about what I had open at the time. No notes in that resource.
6457.SlowSwitchingTabs.zip
0268.SlowSwitchingTabs2.zip