I agree that vinegar, with a dash of salt and a squirt of hand dish soap, slightly diluted with water, is the best, and that should be the starting point before resorting to CLR for heavy deposits.
Even then, vinegar, although mild, is still an acid, acetic acid, so it should be rinsed thoroughly.
Why the salt? The dash of salt acts as a catalyst to make the vinegar work better, and the dish soap is a buffer as well as a surfactant to wash away the gunk.
Again, rinse well (I won't go through all the repeats this time to emphasize the same point) because traces can corrode:
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