OldWikisource contains pages in indic scripts. CSS rules were recently applied to indic language wikipedias to increase line-height for headings due to the upper and lower diacritics used in indic scripts. Line height needs to be increased for oldWS too (probably using the same patches).
The same patches need to be done for commons since they contain such pages too.
Note: This already seems to be in effect at meta.
Refer bug 32826 and bug 30809