Keep main tab fixed
The main tab (with list of titles) is a seperate thing from all the other open tabs (which usually contain PDFs). When I open two many tabs, I frequently loose my main tab, which I however need often to open or search new files. While there are left-right arrows to move between tabs when they extend the size of the screen, I think it would be nice to be able to pin the main tab on the left so that it does not get hidden. I would even argue to give it a distinct colour so that it is easy to find. It would also be nice to have a key command to go "home" to the main tab.