Last Pixel Above Tabs
When in fullscreen if you click on a tab and you're on the very top row of pixels you have a high chance to minimize your browser and always makes me readjust the pointer a bit lower each time i want to click on a different tab.
My suggestion is to extend the tabs to the very top, similar how the Menu button on the top right does it.
This also stand to extending the "back" button to the far left.
There is a setting for this: Go to settings => Browser (in the left menu) => Scroll down to the bottom and check "advanced settings" => Scroll up a bit and check "Disable tab bar's top spacing when browser window is maximised".