"Search Messages" and filters: Add "doesn't begin with" and "doesn't end with"

[TheRupp]

Short summary: For searching and filtering "begins with" and "ends with" currently exist, but "doesn't begin with" and "doesn't end with" do not exist.

This idea is about the window called "Search Messages" and about the window called "Filter Rules" for "Message Filters".

A few certain e-mail-header-fields (Subject, From, To, Cc, "To or Cc", "From, To, Cc and Bcc" and all custom header-fields) can be used for a search or for a filter with the operators (operators is probably not the right word) "begins with" and "ends with". Currently, the operators "doesn't begin with" and "doesn't end with" do not exist even though for all other operators there is a second opposite operator with "not" e.g. "is" and "isn't" or "contains" and "doesn't contain" (or without "not" e.g. "is greater than" or "is less than"). I would like that the operators "doesn't begin with" and "doesn't end with" are added.

Side note: I know that "doesn't contain" can be used right now instead of "doesn't begin with" and "doesn't end with" and that "doesn't contain" is good enough in some cases.

[Jon]

Thanks for submitting an idea to the Mozilla Connect community! Your idea is now open to votes (aka kudos) and comments.