I want to know if I can have 1 single master site that has all content.

Then I want to have multiple child sites with with different members/administrators who can edit content for that specific site, and put into categories that will be displayed on the master. The master will publish all site ...

Same means that you have single folder with files and all sites use these files. So once you upload/delete any file all sites are affected.

Sharing files is required of you share database data, otherwise i.e. user will upload avatar or gallery image in site A and it will be missed in site B.

You don ...

When you say use own files, I'm unsure what you are saying. I want to share the users for single login, comments, etc. The only thing that would be shared is if the write in the forums of slave, and someone responds, they can see that when on master site. Or if they click my groups, my events in ...

If a menu item is of 'Articles -> Single Article' type - it will display article by SEF URL without article ID even without our plugin.

Our plugin can just make URL shorter if this menu item has parent menu item.

MightySites doesn't synchronize data, it shares data: both sites will use same database tables.

Single login will work for separate sites, but they all should share users.

... to database of master site (slave site will use users database tables of master site). Does it mean data will be syncrinized between 2 database ( user data only) or slave site will use data directly master database?

For 2 separate installed joomla site still single sign on will work ?

Thank you :)

I can suggest the following configuration:

1. Run all these sites from single hosting account of main site, so all sites will use same files. Slave sites should be created as parked domains in your hosting panel of main site.

2. All sites will use same database tables, so ALL contents will be same ...

... same database tables, so for sure changes will affect all sites. Each site should have separate contents, in this case different layouts will be applied.
Otherwise you can't use different layouts, or create a single layout override and display different contents by checking current domain manually.

MightySites can help to run these two domains from single hosting account of main site, second domain (i.e. .de should be created as parked domain for main site .com).

Next it will force German language for .de site, so you don't need Falang if it's used for language switching only.

In your description is says
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MightySites is used for 2 main tasks:
1. Run multiple Joomla websites from single hosting account (all sites use same files but different database data).
2. Sharing of database contents (multiple sites can use same database tables, so ...