搜onlyoffice document server的github上的issue，会得到这2个地址
https://github.com/ONLYOFFICE/DocumentServer/issues/67
https://github.com/ONLYOFFICE/DocumentServer/issues/40
It's not clear what we can use for free on this new 4.0 version. I run the docker image and the Chat and Comments were there, but I'm not sure one can use it for free. Is the coauthoring still free like in the 3.x version?

Hello,
Yes, the features you describe are totally free.
The difference in document editing between the Enterprise and Free Edition are Mobile Apps which are not included in Free Edition.
Also the difference is in the connections limit - 20 opened documents (sessions) in an Open Source version and 1 conversion thread,
The comparison of ONLYOFFICE Editions is available here
We would like to note that ONLYOFFICE Community Edition is released under an AGPL license, which must be also applied for your product in case of integration or for your code in case of adding some parts.

它说20个编辑连接数，1个转换线程……一实验，果然到21个就提示来了，然后其他的只能看，不能编辑了。这有何意思呢，一个公司，随便几个文档同时编辑，就会超过20个人啊，还号称免费，还是有限制嘛。
于是在它的源码中寻找突破口……
翻了一下，有server文件夹，有license，config之类，里面有变量，这个变量来自另外一个文件…………
然后再export包中寻找，也有对应的文件夹。save导出包里的文件很复杂，没有规律，而export包里的文件与docker容器中的一致，极好的。