listen for errors from <img> and <video> in the media gallery and
show an error-toast to indicate that the file isn't going to appear
unfortunately, when iOS-Safari fails to decode an unsupported video,
Safari itself appears to believe that everything is fine, and doesn't
issue the expected error-event, meaning we cannot detect this...
for example, trying to play non-yuv420p vp9 webm will silently fail,
with the only symptom being the play() promise throwing as the
<video> is destroyed during cleanup (bbox-close or media unload)
videos unloaded correctly when switching between files, but not when
closing the lightbox while playing a video and then clicking another
now, only media within the preload window (+/- 2 from current file)
is kept loaded into DOM, everything else gets ejected, both on
navigation and when closing the lightbox
* fix crash on keyboard input in modals
* text editor works again (but without markdown preview)
* keyboard hotkeys for the few features that actually work
* js: use .call instead of .bind when possible
* when running without e2d, the message on startup regarding
unfinished uploads didn't show the correct filesystem path
* always enable shift-click selection in list-view
* shift-clicking thumbnails opens in new window by default as expected
* enable shift-select in grid-view when multiselect is on
* invert select when the same shift-select is made repeatedly
