A cursor position jumps in case of a joined annotation in the editing mode

A cursor position jumps to a joined part in case of joined annotation.

Scenario:

1. Open "murine.gb".
2. Turn on the editing mode.
3. Сlick on the CDS annotation with region "join(2970..3413,3412..3873)".
4. Use the vertical scroll bar to open the sequence at coordinate 3874.
5. Click before the last "A" character in the sequence (position 3873).
   Expected state: the cursor is in the clicked position.
   Actual state: the sequence has been scrolled up to position 3380, where the first joined part is located.

A similar issue happens in case a position at the beginning of a joined annotation is clicked (position 2970).