YAML config errors

The console says a .yml file has an error (mapping values, while scanning).

A YAML file has broken indentation or characters; fix the line it names.

Before you start: The file and line number from the error.

Step by step

1. Open the file in Files and go to the line in the error (and the line above).
2. Use spaces only, never tabs, and keep the same indentation as neighbouring lines.
3. Put a space after every colon: key: value.
4. Put text with special characters (: # & * ! | > ' ") in quotes.
5. Paste the file into a YAML checker (yamllint.com) to find the exact problem.
6. Save and restart, or reload the plugin.
7. Keep a copy of the working file before future edits, so you can put it back in seconds.

Check it worked: The file loads without errors.

Why it happens: YAML uses spaces for structure: tabs, missing spaces after colons or unquoted special characters break it.

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