"Prev/Next annotation" will never reach the end if the first/last annotation contains several regions

1. Open "human_t1.fa".
2. Create an annotation: Group name - "1", location - "1..1".
3. Create an annotation: Group name - "2", location - "5..5, 6..7".
4. Open "Annotation highlighting OP widget.
5. Select the first annotation.
6. Click the "next annotation" button.
Expected state: the first location of the second annotation is selected.
7. Click the "next annotation" button.
Expected state: the second location of the second annotation is selected.
8. Click the "next annotation" button.
Expected state: nothing happens (the end is already reached, the second location of the second annotation is selected).
Current state: the first location of the second annotation is selected again.

The same behavior occurs for the "previous annotation" button if the first annotation contains several locations.