Are you using wfLoadExtension explicitly, or require_once, or just relying on composer autoloading?

The extension was loaded by composer autoloading when I installed it via composer. LocalSettings had no effect whatsoever. In MW 1.25+ (1.26 probably as well) I had to manually load composer in LocalSettings:

if (is_readable("$IP/vendor/autoload.php")) {
  require_once( "$IP/vendor/autoload.php");
}

And that way some LocalSettings could take effect. But in MW 1.27 composer is magically loaded before the LocalSettings.

Of course I could manually symlink the SemanticForms-directory to /usr/share/mediawiki/extensions/ but that is somewhat a messy approach to maintain, because

• usually one would expect to install it via composer and it works or
• set additional configurations to adjust functionality and it should work

I know you try the best to make it work, but my guess is that there is something missing to choose when to load the composer. Or is there?

In the meantime I removed SemantcForms from composer and do loading the old way and it works as usual for SF 3.6:

1. git clone of extension, git checkout 3.6
2. in LocalSettings.php: set $wgExtensionDirectory to my symlinked extension directory
3. in LocalSettings.php: requre_once or wfLoadExtension work both

Yep that's what I feared. I do not see any sensible way to make composer autoloading work with extension registration. I have removed composer autoloading from my extensions (SF is not mine).

usually one would expect to install it via composer and it works

... and it should (and it did at some point).

I do not see any sensible way to make composer autoloading work with extension registration.

I feared something like this could easily jeopardise the SMW setup therefore I refrained from making any attempt of using the extension.json (besides some other reasons) for listed https://github.com/SemanticMediaWiki repo's.

@cicalese @Legoktm Some input on this would be appreciated to void confusions and frustrations for a possible future conversion.

Taking @Nikerabbit 's advice, I just removed the "autoload" clause from SF's composer.json file. If anyone knows of a better way to solve this issue, please let me know.