New tab opens after skipping 2 tabs, i.e. after the current and the next in line
A new tab, instead of opening right next to the current tab, has suddenly started popping up after the tab next to the current one i.e. every new tab skips the tab right next to the current tab, and pops up next to it. This is really weird, it hasn't happened before, and it goes agains the conventional rules of tabs opening up either right next to the current or at the end of the tab strip.
Opaite Mbohovái (1)
Do you have that problem when running in the Firefox SafeMode?
http://support.mozilla.com/en-US/kb/Safe+Mode
Don't select anything right now, just use "Continue in SafeMode."
If not, see this:
http://support.mozilla.com/en-US/kb/troubleshooting+extensions+and+theme...