Anki
Drop-in replacementFreeThe same program from the same developer, free, and installed from your app store. Nothing to relearn.
Your files: Syncs your whole collection from AnkiWeb, or imports an .apkg or .colpkg export.
Verdict: Yes
Yes. Anki's download page offers Linux alongside Windows and Mac, and it is free. Your decks come down from a free AnkiWeb account with their revision history intact.
Anki has published a Linux version for years and lists it on its own download page next to the Windows and Mac ones. It is the same program, made by the same developer, and it is free.
The easiest way to get it is from your app store through Flathub, where it appears as a normal entry you click to install. That build is put together by volunteers rather than by Anki's developer, so it can sit a version behind the download on the Anki site. Either one works.
Your collection comes across through your AnkiWeb account. Sync on Windows before you switch, sign in on Linux, and every deck arrives with its cards, due dates and revision history. If you never used AnkiWeb, export your collection to an .apkg or .colpkg file on the Windows machine first and import it on the other side.
Add-ons are the one thing worth checking. Most are written in Python and work on all three systems, but a handful do Windows-specific things. If you rely on a particular add-on, install it early and make sure it still behaves.
The same program from the same developer, free, and installed from your app store. Nothing to relearn.
Your files: Syncs your whole collection from AnkiWeb, or imports an .apkg or .colpkg export.
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