The last Bookmark in a file loses position when Creator is closed

Setup:

• start Creator
• include a 30-line source file in a project and open it in the editor
• set up bookmarks at lines 10, 15, 20
• close Creator

Test 1

1. move cursor at beginning of line 1 and insert <enter> 5 times (i.e. insert 5 blank lines at the beginning of the file)
2. close Creator
3. restart Creator
   Result: the last bookmark is misplaced up by one line

Test 2

1. start Creator
2. select 5 [successive] lines from the file
3. hit <copy> (i.e. copy the 5-line selection)
4. move cursor at beginning of the file
5. <paste> the 5 lines you previously copied (they will now be copied at the beginning of the file
6. close Creator
7. restart Creator
   Result: the last of the three bookmarks is misplaced up by 5 lines

Test 3

1. start Creator
2. select the first 3 lines of the file
3. hit <delete> (i.e. delete the 3-line selection all at once)
4. restart Creator
   Result: the last of the three bookmarks is misplaced down by 3 lines

Test 4

1. start Creator
2. select the first 3 lines of the file
3. hit <delete> (i.e. delete the 3-line selection all at once)
4. now, select and then <delete> the first line in the remaining file (this used to be line 4 before the 3-line deletion above)
5. restart Creator
   Result: the last of the three bookmarks is misplaced down by one line

PS:
My conclusion (for what it's worth): the last change in position that occurred to the last bookmark in a file before closing Creator does not get saved when Creator closes.

PPS:
I tried this with breakpoints also, but [it seems to me] that breakpoints do not exhibit this behavior