As of August 8, 2017, the length limit for tags went from 25 characters to 35 characters. So now is a great time to allow inconveniently compressed tag names to stretch out a bit...
Perhaps we could collect here list of tags which now, after the character limit for length of tag name has been extended, could be spelled in full instead of a shortening. (This answer is CW - feel free to edit in here various tags that are currently shortened.)
Among possible suspects are the tags with name of length 25 - they can be found by this SEDE query: Tags with given length of name. (However, not all shortened tags use exactly 25 characters. Two examples are computational-group-theo or infinite-dim-manifolds.)
- combinatorial-group-theor $\to$ combinatorial-group-theory
- combinatorial-number-theo $\to$ combinatorial-number-theory
- computational-group-theo $\to$ computational-group-theory
- computational-number-theo $\to$ computational-number-theory
- differential-galois-theor $\to$ differential-galois-theory
- infinite-dim-manifolds $\to$ infinite-dimensional-manifolds
- symmetric-monoidal-catego $\to$ symmetric-monoidal-categories
- transcend.-number-theory $\to$ transcendal-number-theory1
1There is a separate discussion whether there could be a better name for this tag: The tags (transcendence) and (transcendental-number-theory).