Stuck formatting in CKEditor

[webian]

Reproduce:

1. apply any formatting (bold, italics, etc.) to a word.
2. click on any unformatted part of the text.

Result:
the formatting applied in step 1. is still selected. Then, to reapply formatting to unformatted text, you must click the button twice: once to deselect it and again to select it and apply the formatting.