The day ununifying history for back & forward buttons in the dropdown list will be restored even through an addon, maybe this addon will have a real "potential" & interest. noun addon not supporting it anymore.
Upon updating to v46.0 (or 46.0.1 - I'm not quite sure), the history items number got messed up. It works fine within the same session but when you restart the browser you only get the last 11. Not 10, not 15 (which is the default value), 11. Another incompatibility case with TabMixPlus? Who knows? Very, VERY frustrating! Firefox's developers are to blame of course. This add-on would be redundant if only they allowed tweaking the item number through about:config. If memory serves, it used to work that way in the past.
EDIT: Never mind V@no, I found the culprit - It was "browser.sessionstore.max_serialize_back". For some reason (Did I accidentally reset it? I don't think so) it went back to its default value, 10. The moment I set it to "-1", the problem vanished :) More info on the subject @ https://support.mozilla.org/en-US/questions/1057730
5 stars for the core functionality. -1 star for the popup that shows no matter what i'm doing - watching a movie, playing a game, you name it. It's not that important for me to know that this addon has been updated! This option should not be on by default unless it can somehow avoid full-screen activities (which I doubt is possible).
Changes log page always had an option to disable it showing after each update. Since v1.2 the default setting is to show a notification popup instead of opening a new tab and also can be controlled within addon's options page.
I had to go back and drop the rating after an initial 4 star rating. After using it for a while it really didn't give accurate histories at all. Since I always surf with many tabs open it also confused them instead of giving the individual history of each tab. My main use for it would have been to find key pages on galleries and even that didn't work.
Maybe it can be fixed to give accurate histories- but until then it isn't ready.
** Edit** I will see if I can email you and see if a solution can be found. If one can naturally I will delete this review and give it a good one.
I'm using it myself on my main browser where I keep about 70 tabs open at all times. Some tabs have over 500 item in the history and I've never ever experienced anything you've described. Perhaps it's a conflict with other extension in your browser. Facebook for example manipulates history when you browsing gallery, when it closes picture overlay it automatically jumps to the beginning of the history, leaving all photos that you just watched in the "forward" history.
Perhaps you should've contacted the author with a bug report before giving bad rating...