This issue only happens in Internet Explorer 8, 9 and 11 (at least), and it can be reproduced in Confluence 5.x.

Steps to Reproduce:

This issue happens in two scenarios as you can see below.

Scenario One:

1. Edit a page in Confluence.
2. Please write a few lines of text, or it is fine if the page already has some contents.
3. Try to click on the gray area below the bold button, or any other gray spot as you can see in the screenshot attached. One click will do the trick.
4. Click on the Bold button, as in you wish to type with bold format.

Scenario Two:

1. Edit a page in Confluence.
2. Please write a few lines of text, or it is fine if the page already has some contents.
3. Try to press Italic button, then press Bold button, and at last press Italic button again. or this can be in Bold > Italic > Bold order as well.

Expected Results:

The cursor must remain on the last place it was. And there should be no change in the location of cursor in the text.

Actual Results:

When trying Scenario one and two, the cursor jumps to the beginning of the first line.