My last commit here (https://github.com/hypothesis/h/commit/5f56d8ad0424f11e52736fd9a1f9b8c30ab0f6a1)
has broken this function for or operators, because it forgets to apply the rule.format() call
to the search terms

I.e the user field uses this to transform the username to the full user format (acct:username@domain)
And because of this the user streams were broken.

Fix #1391