This add-on is an updated version of the original External Editor add-on (link) by github user pointtonull.
Next time you press Ctrl + Alt + X while editing a field it'll open your configured editor. (The shortcut is configurable)
Note: When you press the shortcut and nothing happens it may be because there is a conflicting shortcut. Try setting a different shortcut in the add-on config and reopen the editor window for the changes to take effect.
It allows you to specify your editor of preference.
For Windows users, remember to escape (duplicate) the backslashes in the path (json uses backslash as a special character):
{
"editor": "c:\Program Files\Notepad++\notepad++.exe"
}
Problems, Bugs, Errors, Improvements
If you have an idea for an improvement or encounter a problem please create an issue on Github.
Support my work
If this add-on is useful to you please consider buying me a coffee:

Updates:
2026-04-16: Fixes the editor not launching on Windows when configured with a full path
2022-05-17: Added config option for file extension of the temporary file created when editing note contents
2022-04-25: Adjusted default shortcut for mac, add more information on setup in config
2022-02-06: Added compatibility with Anki 2.1.28
2022-01-28: Changed how editors can be configured
2021-11-5: File editor launch commands can now be specified as a list to allow white space in arguments (e.g. ["command", "arg1", "arg with spaces"]). (Contribution by github user jack-faller.)
2021-9-22: Initial Release (Update for Anki 2.1.45)