iPad Pro...with the Apple Folio Keyboard and a Logitech mouse

My iPad Pro and Folio Keyboard work great. So I tried for a trifecta by buying a Logitech Anywhere 2S mouse. The mouse is highly recommended for the iPad.

Setup was a breeze. But when I starting typing a query in Safari, I noticed that a bunch of characters ended up blank. I type a specific character like "L", , and there's nothing. I tried typing on a Mac forum - same problem. Certain alphanumeric characters just don't work.

I toggled Assistive Touch off, and suddenly everything's back to normal.

Other users are apparently using third party mice on iOS 13 without incident. What am I missing?

Thanks!