@b4n I applied both of your patches, dropped the other file modifications from your patches and added the extra NULL parameter to the `_provided()` functions. This is the "Add changes from Colomban" commit.
Then I removed some stuff unneeded for this PR from pluginextension.h/c and made various changes we discussed here (please let me know if I forgot about something).
I originally didn't get why ``` +GEANY_API_SYMBOL +gboolean plugin_extension_autocomplete_provided(GeanyDocument *doc, PluginExtension *ext) ``` functions were made part of the plugin API so I removed them but then I remembered it's because of the explicitly provided `ext` parameter so I re-added these to the API in the last commit.
Documentation is still missing but if these changes look good to you, I'll start working on it.