if the current typing cursor location is off screen, typing does not bring it into view. this can result in garbage characters in surprising spots in your program. you can get the cursor out of view by scrolling, or sometimes in using search.
thanks!
@RonJeffries thanks for picking this up! This is a regression in the move to the new code editor, will fix
@RonJeffries I tested this and typing did bring the cursor back into view. Does it always happen or just sometimes?