@jaw1 also had a discussion about this matter before logging the bug report, I added some additional information here to that.
It’s a little hard to quantify the variance in behaviour, but hopefully I’ve documented okay. I suspect there were a few behaviours that changed around this, but I can’t seem to work out what they are as I use Obsidian with muscle memory and struggle to work out what’s changed.
One obvious one is as @jaw1 has documented. Here’s videos of both 1.5.3 and 1.5.8 in the sandbox vault, with comments on the difference: