Bookmarks panel is not working properly

Today I install new version (1.6.15.0) via updater and Immedeately I encounter a problems.
for example the bookmarks panel... let's me explain.
1. I resize bookmarks panel to appropriate size
2. click View -> Show/Hide Bookmarks
3. the panel is hide
4. click again View -> Show/Hide Bookmarks
5. the panel won't show, but when I try to resize the panel I can resize
6. start again... It'ds not working again (the panel is hide but won't show again)