The TST sidebar still shows on screen when entering full screen mode (F11) on Firefox 57.
TST sidebar should autohide.
TST sidebar stays visible.
It is impossible by TST 2 because there is no WebExtensions API to do that. Basically WE disallows addon to show/hide its sidebar without user's action on its custom keyboard shortcut (F1 for TST) or clicking on the toolbar button.
Would it be possible to have a configurable option to toggle fullscreen with the same button as TST visibility (F1)? Only one user interaction would be needed then.
I found a userChrome.css workaround:
display:none !important;
width: 0px !important;
}
I added wdnz's workaround to the wiki with an additional hiding of #sidebar-splitter.
I close this because this is out of the range of WebExtensions-based extension.
Most helpful comment
I found a userChrome.css workaround:
main-window[inFullscreen] #sidebar-box {
display:none !important;
width: 0px !important;
}