Personally I like the `ft/...` format using "/" for divider. However, it does not play with other software especially when the url is involved (e.g. the branch name collides with url path). This issue fits loosely similar problem to file naming to avoid problems (e.g. avoid " " (space), "-" (dash), or use of any weird characters as part of filename. This is the reason why you may find a lot of files named with "_" (underscore), especially in place of a space.

This raises the question of using "-" or "_" for divider. Keep in mind there are words that may have "-" (e.g "self-expression"). And as far as I know there are no words that have "_".

In summary: And so I have decided on using "_" as my divider and plays well with other integrated tooling for future robustness.