In the ACP, an administrator can change some signature settings, such as the maximum number of characters.

However, there is no option to limit the number of line breaks (<br/> in HTML). Some users can have a "short" signature in terms of number of characters but a long signature in terms of lines (eg: someone types a poem as signature, with short sentences but numerous lines). Consequently, the signature can alter the readability of topics because its height is too high, not because of the number of characters