Symbols
A symbol is a reusable clip with its own internal timeline that you place, and re-place, anywhere in the project: edit it once and every instance updates.
A Symbol layer carries its own embedded layer tree and its own timeline, separate from the scene's. Edit the artwork or animation inside a symbol once, and every place you've placed it in the project picks up the change.
Creating a symbol
Add Layer ▸ Symbol makes an empty one to build from scratch. Convert to Symbol wraps existing layers into a new one in place. Either way it lands in the project's Library, and dragging a copy from the Library onto the canvas places a fresh, independent instance with its own layer id.
The internal timeline
A symbol's own timeline runs from frame 1 to frame 24 by default, both ends are adjustable, at its own frame rate, or the scene's if you leave that at 0. Double-click an instance on the canvas, or its row in the Library, to step inside and edit it: everything you draw or animate there lives on the symbol's own timeline, not the scene's, and a breadcrumb lets you step back out. Symbols can nest inside other symbols, up to eight levels deep.
Frame actions
On the scene timeline, an instance's internal playhead does not simply run: it is driven by frame actions. Play starts it forward from a chosen internal frame; Stop holds it on whatever frame the preceding Play reached; Loop cycles a range. Right-click an instance's row on the Timeline for Play Symbol, Stop Symbol and Loop, among the other frame actions.
Group markers are named, coloured ranges on the symbol's own timeline, each carrying its own frame actions. The Variants panel lists an instance's group markers, and clicking one drops the matching Play and Stop actions onto the scene timeline for you.
When nothing on the scene timeline tells an instance otherwise, its playback mode decides what happens at the end of its range: Single, Loop or Ping-Pong, with Loop as the default. It is stored with the symbol and travels with the project, but Early Access exposes no control for it, so every symbol plays on Loop until a frame action says otherwise.
The symbol library
Renaming an instance also renames its library symbol and every other instance sharing that name, in one step, so instances of the same symbol can't drift into different names. Library ▸ Purge Unused clears out symbols nothing in the scene references any more, after showing you the count first.