if the height of each row is controllable, my idea is to determine whether the expand button is displayed by judging the height of two rows. The idea of
is
1, set the height of the parent element to the height of 2 rows, and hide the excess of the child element with overflow:hidden.
2. Control whether the expand button is displayed by determining whether the height of the child element is greater than the height of two rows.
online demo

think of a stupid way to loop out the last tag until the height of the parent element is less than the specified height

first of all, the selection of tags should not be random, but more, so there is not much need for you to align.

secondly, users must be induced to choose a label of 2 words from the point of view of product operation, otherwise users will have to hang up if they enter dozens of words at random.

on this basis, you only need to display two lines of tags, and then control overflow:hidden to display the rest.