Back / forward navigation by swiping off the left/right borders
There is at least one more web-specific pain point that's not addressed - the back / forward navigation by swiping off the left/right borders (instead of pressing back / forth buttons):

ouch! every now and then this safari navigation comes back to bite me. Honestly its a pain that a browser has implemented and enforced such a high level concept 😢.
Since the pages are already rendered in the back case at-least it leaves very less opportunity to what we can do.
I'll try thinking something, and am open to suggestions
What comes to mind is intercepting these swipe gestures and disabling entering transition in that case. Getting rid of this glitch (by glitch I mean showing entering transition when page was already displayed in its final appearance) would be good enough, I don't think we can do any better.
One more idea to explore (I don't know if it will work) - preventDefault() this off the screen swipe and then programmatically trigger history back (or forth, if that was the case) move.
Or maybe just preventDefault() and that's it, as a quick hack. If a user really wants to go back, he'll press back button on browser chrome or will use website navigation.
is there an event for these swipes?
There is no event- although you can sense it occuring as raw touch events on the document. preventDefault won't help you here, there is literally no way to prevent navigation that I am aware of. Once again the joy of Safari bites back... :(