I have recorded the problem here: https://vimeo.com/454995903
I'm holding down Shift key, and trying to move the layer to snap to the beginning of the other layer.
As you can see, I narrowed down the problem to the text layer above it, it seems like the text layer's opacity key frames are causing this issue.
How do I fix this? Every time this happens, I have to zoom in maximally on the timeline and move the layer frame by frame to get the layer adjusted to the beginning of the other layer, because I don't know which other layer is causing this.