closes#12015
refs 95880dddeb
- The bug was caused by falsy plaintext field assignment to empty string `''` when the html content was `null`. Because of the `setEmptyValuesToNull` function (referenced commit), there is no sense to assign empty string value to plaintext property, because it would still end up being `null`
- The `''` -> `null` conversion was confusing the model layer to think that some fields were changed, where in reality none did. This in turn lead to a bug with falsy cache invalidation
ced3e28d60