Since there were no answers providing you with shortcuts, I'd like to answer with another workaround based on the Field Calculator.
Start editing string values in the attribute table and insert a special character (I chose
_ for the example) that will serve as a delimiter character to wrap to a new line:
Once you have edited the values, open the Field Calculator, select
Update existing field, and copy this as
"names" is the field name I edited):
wordwrap( "names", -1, '_')
Click on Ok. Now you have your attribute table with multi-line values. As you mentioned, labels are able to deal with such values, as well as other tools such as identify.
The approach I exposed is good because in a single action (calculating values from an expression in the Field Calculator) you get what you need.