Sounds like you ran low on ram.Good Afternoon,
Well, I had intentionally put stress on memory by opening so many tabs, as this was confirmed when I checked out the memory in Activity Monitor. Pressure graph was in the yellow with sections in red and heap loads of swap used. By the way, before switching to Mail I paused each video in order to reduce cpu load.
I've just repeated the experiment and this time I did not get such a long delay. Memory pressure was still in the yellow and spiking red, but switching between apps was clunky. I imagine rightly or wrongly that things would be mitigated by a faster ssd in more recent Airs, and I suppose whether working on a Mac with such high memory pressure is acceptable or not is a personal preference. Anyway, 20 tabs of video is something I would not normally be doing so I'm not really going to delve into this anymore!
b en
Did you just run youtube and mail?
A faster ssd barely substitutes for ram, that is a bit of a myth.