The new Insights selection menu on Mobile should be temporarily hidden when dragging the selection handles so we can see what we are selecting.
(I can't confirm, but I think that is how it used to work).
Thank you for reporting. I've created a case for this.
Yes I just noticed that same thing today. Glad a case has been opened.
I am finding this to be an issue on my Android phone, as opposed to my Android tablet (perhaps due to less “real estate” on my phone).