In my application I'm trying to make use of newly added multi-document transactions feature.

I got the following error:

Total size of all transaction operations must be less than 16793600. Actual size is 16793817

Why this limit was not specified in documentation? And do you have plans to increase the limit?

During testing I also run into several other problems, like unexpected "Transaction aborted" errors when I had a few thousands of simultaneously open server sessions. Is there any document (like blogpost or maybe some internal docs) with a description of all limitations?