If a user extends a clip beyond the footage's length, they can
choose whether they want a black frame, the last frame continued,
or for the footage to loop infinitely (same for extending earlier
than the start of footage).
* .arg() doesn't handle plurals, replace %1 with %n and pass number to tr(), but only if there is an accompanying word for that we want singular/plural translations and only for whole numbers.
* Qt's translation methods only accept integers and we don't know what grammatical number form would be correct for floating-point numbers in different languages anyway.
* Add optional 2nd argument to SliderBase::SetFormat() to activate deferred plural handling:
SetFormat(QT_TRANSLATE_N_NOOP("olive::SliderBase", "%n unit(s)"), true)
* Generate en_US.ts with lupdate's -pluralonly option. Only source strings that require plural handling need to be translated (as long as the source language is American English).
Not accessible through UI yet, but ported Footage node to it
(previously we used a hack to ensure Footage textures were
cached, now it's a formal infrastructure).
itsmattkc