Hi. Thanks for the review. Seems that you're not the only one that has this problem. Sadly I don't think there's a solution for it because it doesn't seem to be a problem created by the code from the addon but most probably after a Firefox Update.
See this thread for more info: https://github.com/ReDEnergy/SessionSync/issues/103

As much as I hate the issue, I can't really implement a solution for it because there is nothing wrong with the addon itself. If you try and open the addon view inside the Windows Mode or the Tab Mode you will see that the scrolling works just fine. The issue is related to the Firefox profile you have I believe. Sadly it seems that Firefox updates constantly keep corrupting (for various people) the profile. This might also be a problem created by the same issue. I understand your frustration but there's literately nothing I can do, if the same code works in Tab Mode / Window mode (CTRL + SHIFT + V or CTRL + SHIFT + U) then it means that Firefox somehow broke the Panel mode (and it's not reporting right the information inside). If you would install the addon on a clean profile you will see that everything works as expected.

Thanks for point it out, but unless I can somehow find the issue and investigate more about it, there's nothing I can do. Again, looks like is not a problem of the addon, but I might be able to somehow do things differently to avoid this Issue I will try.

Hi. It's a little hard for me to understand why the complain having in mind that the addon is specifically built for manual saving of sessions AS BOOKMARKS. There's no way that would be automatically because the addon would make firefox unresponsive every 10 seconds otherwise. Saving tens of bookmarks or even hundred is not acceptable for performance reasons. Yes, the addon has another small feature that saves in background everything once ever 15 seconds (or whatever you set), but that's clearly not something full featured and can't be compared with an auto-save session addon. I totally understand that the addon may not be for everyone, but I'm not even trying to promote it to those that want auto-saving :|. The description says that "you can save sessions as bookmarks" not that they are automatically saved.
This addon is intended for those that want control over what and when they want things to be saved and on top of that is made for management using the bookmark system. Don't want to be mean, but I'm not trying to sell the addon as what it's not, so giving it a 1 star for something that is not even suppose to be doing is not really ok.

Hi. Even though you might expect that as a main feature the addon description clearly states that you have to "Save them", at least that's the main reason of the addon. Now, I really don't know how to describe that better. Getting a 2 star rating for not having a feature that I never intended to add is quite odd.

Of course, there is a secondary aspect of the addon, the history tab will constantly save each 15 seconds (or how many you set) your current active session and you can find it there in case the browser crashes.

Of course things might not be exactly what you may expect, but that I can't change. The addon was designed to work with bookmarks and saving the session constantly into bookmarks would have been impossible. The addon main purpose is to be a session management tool, not an auto-saving session (although it does have that as well in the History tab)

Hi. I do understand that you may expect something different based on what you are used to, but only because an addon is designed to do something in certain ways does not mean that's a bad product. The addon does what it was suppose to do, and of course it has a few limitation imposed by the bookmarking system that is used for storing data. The whole idea of the addon is to have session stores as bookmarks. Because of this, there are some limitation that you have noticed.
Yes - sadly each window is treated as a sort of separated session when saved into bookmarks. You can either save windows one by one or save all of them at the same time. From my own experience there is clearly not a best description of what "session" means for each one of us. For some, different windows should be treated as separated contexts while for others consider all windows to be part of the same session. No matter what decision I take, if I don't have good support for implementing the features required into the bookmarking system for sure there will be missing features.
I clearly do not expect the addon to be a good fit for everyone out there because the main feature is actually support for manual saving of sessions (as windows mostly) and rename them according to your preference.
If an addon does not do what you would like it to do, I don't think it deserves right away a bad rating, it's just not something that works for you personally, maybe. All I can say is that although there are a lot of missing features that I might add in the future, the addon does what it was suppose to do.
The addon clearly was not made to compete with Session Buddy or other session masters out there, the addon main responsability is to store sessions as bookmarks and provide you with an easy to use interface to maintain a list of them.