Gelatin's crazy slogan (3,4)

I believe the answer is:

tag line

'slogan' is the definition.
(I've seen this before)

'gelatin's crazy' is the wordplay.
'crazy' indicates anagramming the letters.
'gelatin' anagrammed gives 'TAG LINE'.

(Other definitions for tag line that I've seen before include "Something memorable one might say" , "Catchphrase (mainly US)" , "End of joke" , "Slogan" .)

I've seen this clue in The Times.

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