[Study] [Feature] Add Engine line as Variation

Hi,

I have a suggestion/feature request, some analysis tools (for example chessx) allow adding engine lines that have been calculated already to the game as a new variation. This has the added benefit of saving potential processing power, as lines don't have to te recalculated*, but it is also super convenient.
Maybe a "+" sign at the right edge of each line the engine calculated to add the current calculation as a variation

Thanks to the developers for the effort, regardless :)

* = I.e. after calculating a novel variation to a deeper depth, clicking on the engine line only adds the first move as a variation, upon stockfish starts recalculating the old line

Thanks, github.com/ornicar/lila/issues/5173 is recorded

Thanks, making engine calculation sticky is certainly also a nice idea/feature. It's not quite what I mean, however - you'd still need to manually enter the engine line on the board

I see what you're saying too, however a live analysis keeps changing, so while the analysis is live there's not much point in adding it.