I updated my firefox browser on October 6th and ever since then, whenever I press ALT to switch to a different application (I use ALT + Tab to switch windows) I go back in a tab's history. This never happened before and I'm not sure how to go about disabling whatever function this is. I've checked in the about:config section of firefox but I don't know which of these options is for this function, if it's even in here. Any advice or help would be appreciated!