Okay, now here's a throwaway post where I can experiment with those three lines. Hmmmm.
Click once and a horizontal dashed line appears, with a dashed box below it. They do not appear to interact with my typing at all.
Click twice on the three lines, and another box appears below the first one, followed quickly by five more when I try to click back into my text entry to report on my second three-line click.
The second through fifth boxes are larger than the first. The sixth through ... goodness me, there are ten of them now ... are bigger again. They do not appear to do anything at all.
I'm going to try to post now. Let's see what happens.