Generate backlinks for links embedding sub-headings as well

[DawMatt]

Backlinks appear to only be generated for note level backlinks, not sub-heading backlinks.

e.g. the following link, which is generated by right clicking on a note and selecting "Copy markdown link", has backlinks generated by the plugin

[Deferred Works Planning](:/96aff681f2f34a90b305f1feeb1cf020)

e.g. the following link, which was generated by right clicking on an outline heading within the joplin-outline plugin, can be navigated to using the Joplin app but will not have backlinks generated by the plugin

[Deferred Works Planning#20210506 1300 Deferred Items Discussion](:/96aff681f2f34a90b305f1feeb1cf020#20210506-1300-deferred-items-discussion)

Can you please add support for sub-heading level back links to the plugin?

[ambrt]

Thanks for pointing it out, I'll see what can be done.

[ylc395]

@ambrt Is it OK if I submit a PR?

[ambrt]

Hi @ylc395, if you are still interested writing PR then i'm open to it

[ylc395]

I implement it in my new plugin: https://github.com/ylc395/joplin-plugin-note-link-system