Krita
Close matchFreeFree painting app with a real animation timeline and onion skinning. Good for frame-by-frame work, weaker for tweening and rigs.
Your files: Cannot open .fla or .xfl files. Imports image sequences and PNG exports.
Does Adobe Animate run on Linux?
Verdict: No
No. Adobe Animate is a Creative Cloud app for Windows and macOS only, with no Linux build and no browser version. Krita and Blender cover the drawn animation, though neither works the way Animate does.
Adobe's technical requirements for Creative Cloud apps cover Windows 11 and recent macOS releases. Animate is on that list and Linux is not, and there is no web version to fall back on the way there is with Photoshop.
Animate is the descendant of Flash, and that history matters when you look for a replacement. It does frame-by-frame drawing, tweening between keyframes, bone rigging, and publishing to HTML5 Canvas, video or a game engine. No single free Linux program does all of that.
Krita gets you closest for drawn animation. It has a proper timeline, onion skinning and frame management, and it exports image sequences or video. What it does not have is Animate's tweening and symbol system, so cut-out style animation means more manual work. Blender's Grease Pencil is the other option and handles drawn animation inside a 3D scene, which is a different way of thinking but very capable.
Your .fla and .xfl project files will not open on Linux. Before you switch, export what you need as video, as image sequences or as HTML5, and keep the original artwork files somewhere safe.
What to use instead of Adobe Animate
Blender
Different way of workingFreeIts Grease Pencil tool draws and animates in 2D inside a 3D scene, with rigging and interpolation. A large program to learn.
Your files: No .fla support. Imports SVG artwork and image sequences.
Inkscape
Different way of workingFreeFor redrawing the vector artwork that lived inside Animate, then handing it to Krita or Blender.
Your files: Opens SVG files exported from Animate. Cannot read .fla projects.
This doesn't have to stop you
One stubborn program doesn't have to decide the whole question. You can keep Windows on the same PC and restart into it only when you need Adobe Animate. Everything else you do can move.
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