download_lines is a very small value, for a normally sized terminal is exactly 5. This was the cause behind the download pane glitch, 5 was used as *column number* for the reflow. Now, to be honest, the exact width passed to wrap_page is not important. wrap_page will only wrap the size string, which we know is less than or equal to FMT_SCALED_STRSIZE-1 (6). We could also hardcode the value eventually, but using download_cols reads better.

improve the download procedure by pre-filling the minibuffer with /tmp/<file-name>. At the moment ``/tmp/'' is hardcoded. Idea from a conversation with hurricane, thanks!

If tab-bar-show is -1 hide the tab bar permanently, if it's 0 show it unconditionally. If it's 1, show the bar only when there is more than one tab.