Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
Q&A for work
Connect and share knowledge within a single location that is structured and easy to search.
The tags help box (shown when editing tags) says tags can contain +, but when I type a tag like "lost+found", it tries to use two tags, "lost" and "found".
Tags can contain plus, but only at the ends, e.g. c++
In general you should avoid this.