REGRESSION: Line edit does not handle mouse events properly

I have a line edit in a custom control that I've made, and since version 4.6.3 the cursor disappears if I highlight text and then click somewhere in the line edit. For example, if there's text and I do NOT highlight anything but just click on various locations in the text the cursor moves as expected. If I highlight a section of text with the cursor and then proceed to click a section of text, the highlighting disappears as expected but the cursor is gone and lost forever. It's really there, because if i type the characters show up in the expected locations, but the flashing cursor symbol is not there.

It behaves properly in 4.6.2, which is the version I am using because of this 4.6.3 bug. If it helps, I noticed this bug several months ago when I was using "bleeding edge" versions of 4.6.3, but now that it's officially released the bug is still there, so you should know about it.

Note: The first image is the highlighted text with the cursor, the second image is after clicking somewhere inside the highlighted area, notice the cursor is gone.

Again, I know it's not my own fault as a programmer, because this has been working fine until 4.6.3