Owncloud 10.0.2 Asset pipeline does not seem working


I upgraded from Owncloud 9.1.5 to 10.0.2 three weeks ago.
Everything works except asset pipeline.
I have these parameters in my "config.php":

'asset-pipeline.enabled' => true,
'assetdirectory' => '/var/www/owncloud',

But the "assets" folder remain empty.
I checked all permissions, and they seem right.
I have no error message.
Calendar and contacts apps are activated.

I tried different workarounds without success.
I can't figure out where the problem is.

Thanks for help

I did the following search https://github.com/owncloud/core/search?q=asset+pipeline&type=Commits&utf8=%E2%9C%93 and found https://github.com/owncloud/core/commit/9b212befa0e72ea6423e14157833053d5bfeda8f

Looks to me like it is a expected behavior.

So there is no assets pipelining any more? Is there another way to make ownCloud more lightweight? Example: My login page has a page load of almost 800 kB, simply minifying of js could save some bandwidth without having the danger of combining scripts and potential breaking of plugins or core features.