I usually like opening a lot of new tabs, and avoid closing them until the end of the day or my work session. During my day, I end up browsing about multiple topics as I multi-task. Thus, I have groups of tabs which are usually next to each other. It would be nice to have a "Separator line" to demarcate the groups of tabs.
For example, this is how my tab-bar looks like currently:
With separator, it could look like this:
This makes it very easy identifying where a desired tab would be.
PS: No ability to add images in the forum?? That's bad.