There are just over 500 entries tagged 'framework' on SO, and just over 400 tagged 'frameworks' (or maybe vice versa). I rather suspect one such tag would do - I would probably select the singular over the plural, but I have no strong opinions on that issue.
Many of them are asking about a given framework, but don't have the given framework as a tag.
Which currently has the tags
The questions that do have the given framework as a tag, don't really need either tag. They also usually have the
[framework] tag immediately following the the name of the framework. Which suggests that they may have put the
[framework] tag on without thinking about it.
There are some that seem to be appropriate to have
[framework] as a tag.
Then there are those that apparently just added the tag because it was there.
I'm going to go out on a limb here, and question whether we even need either tag.
Just scanning the titles I don't detect a distinction in usage. I'd say merge them to the singlular tag.
The plural usage probably is used to indicate that the question involves more than one framework, possible for comparison or contrast purposes. This is a common problem among such general-use tags. Compare also:
Plural more common:
- packages (115) vs package (59)
- programming-languages (853) vs programming-language (1)
- functions (427) vs function (420)
- methods (236) vs method (174)
- namespaces (293) vs namespace (162)
- variables (439) vs variable (180)
Singular more common:
- language (268) vs languages (52)
- class (802) vs classes (223)
- library (1101) vs libraries (16)
- file (928) vs files (760)
Maybe something else needs to be done wrt the plurality issue.
Just merge them, any possible confusion should be cleared by the other tags of the question.