Sharepoint 2019 - force mysite subsites to get custom css

Question

I set a custom css at

• /_layouts/15/settings.aspx (root site collection from mysite webapp)
• Look and Feel > master page
• alternative css

css-file is located at /_Layouts/CSSRegistration/...* .css. This is set for both WebApps (main intranet :80 and mysites :12***) At the main intranet webapp it worked and all subsites got the right css

But for some reasons the personal sub sites from the mysite webapp dont inherit the css from the root site collection. Also in the website settings of the mysite root site collection there is no checkbox to force inherit css to all subsites.

Any ideas what i can do to get it worked?, that the subsites (of mysite webapp) will get the right custom css file?

Additional information:

Mysite - root site collection

• Sharepoint publishing features (site collection level) is activated
• Sharepoint publishing features (website level) is activated

Mysite - subsite collections

• publishing features at site collection and website level are NOT activated

• maybe thats key point of failure, but how can i be sure that all existing AND in future created mysites have activated features on site collection and website level?

• deleting and recreating a mysite did not work too

thanks for any suggestions =/

Answer 1

The alternative css settings is on the site collection level. If you only set alternative css in the root site collection, it would only work in the root site collection.

You have to set the alternative css for all the site collections(nee to activate publishing features at site collection) to make it work.

Answer 2

• WebApp - Mysites
• --- Root site collection
• --- --- my
• --- --- --- My site 1
• --- --- --- My site 2
• --- --- --- My site 3
• --- --- --- ...

is it correct that in this case i have to activate ON EACH my site subsite collection (>= 50 my sites) the publishing feature (site and site collection) MANUALLY ??? ok, i can use powershell. But, what is about the newly created my sites? i did some tests and delete/recreate a personal mysite and the problem with disabled publishing feature and not inherited custom css appears also. thats why iam a bit confused about that way to solve it. =/ regards