These changes were part of the core CSS and when I check oldwikisource, I see the CSS changes you request are there.

The problem you are likely seeing is that "lang" attributes aren't being set correctly. Can you point to a page where this works on meta as expected and a page where it doesn't work on commons?

(Adding Niklas and Siebrand since they probably have more clue about this.)

(In reply to comment #1)

The problem you are likely seeing is that "lang" attributes aren't being set
correctly. Can you point to a page where this works on meta as expected and a
page where it doesn't work on commons?

Working on meta: http://meta.wikimedia.org/w/index.php?title=%E0%A4%AE%E0%A5%81%E0%A4%96%E0%A5%8D%E0%A4%AF_%E0%A4%AA%E0%A5%83%E0%A4%B7%E0%A5%8D%E0%A4%A0&uselang=hi
Not working on commons: http://commons.wikimedia.org/wiki/File:Hollow_Horn_Bear_(%E0%A4%96%E0%A5%8B%E0%A4%96%E0%A4%B2%E0%A4%BE_%E0%A4%B8%E0%A5%80%E0%A4%82%E0%A4%97_%E0%A4%AD%E0%A4%BE%E0%A4%B2%E0%A5%82).jpg
Not working at oldWS: http://wikisource.org/wiki/%E0%A4%B9%E0%A4%A8%E0%A5%81%E0%A4%AE%E0%A4%BE%E0%A4%A8%E0%A4%9A%E0%A4%BE%E0%A4%B2%E0%A5%80%E0%A4%B8%E0%A4%BE

Note: Setting uselang as hi (or any other language with the lang-specific height increase) makes the pageheading appear correctly. See the difference between http://wikisource.org/wiki/%E0%A8%AC%E0%A9%81%E0%A9%B1%E0%A8%B2%E0%A9%8D%E0%A8%B9%E0%A9%87_%E0%A8%A8%E0%A9%82%E0%A9%B0_%E0%A8%B8%E0%A8%AE%E0%A8%9D%E0%A8%BE%E0%A8%B5%E0%A8%A3_%E0%A8%86%E0%A8%88%E0%A8%AF%E0%A8%BE%E0%A8%82 and http://wikisource.org/wiki/%E0%A8%AC%E0%A9%81%E0%A9%B1%E0%A8%B2%E0%A9%8D%E0%A8%B9%E0%A9%87_%E0%A8%A8%E0%A9%82%E0%A9%B0_%E0%A8%B8%E0%A8%AE%E0%A8%9D%E0%A8%BE%E0%A8%B5%E0%A8%A3_%E0%A8%86%E0%A8%88%E0%A8%AF%E0%A8%BE%E0%A8%82?uselang=hi for example.

It appears this is also the case for single-language projects such as hi-wp. Since the heights have been specified per the lang attributes, going to http://hi.wikipedia.org/wiki/%E0%A4%AE%E0%A5%81%E0%A4%96%E0%A4%AA%E0%A5%83%E0%A4%B7%E0%A5%8D%E0%A4%A0?uselang=en shows that the height-increase is not to be seen and the diacritics are again hidden.

Sorry for the late response.

Does this problem basically boil down to Bug 34514 ? If yes, should this be marked as a dupe of that?

Long letters gets cut because of

h1, h2, h3, h4, h5, h6 { overflow: hidden; }

This was set because of Bug 26449. Bunching cannot appear on first heading, so overflow:hidden isn't needed here. The default value overflow:visible can be set by

#firstHeading { overflow: visible; }

in skins/common/commonInterface.css

(In reply to comment #4)

Long letters gets cut because of

h1, h2, h3, h4, h5, h6 { overflow: hidden; }

I'm not sure, but I think that isn't the entire issue. Even if the overflow is set to visible, the characters will probably cut through the line below due to font renderings, and for lower headings, they might even cover the plaintext line below. This problem was previously handled in bug 32826 and bug 30809 via setting the line-height for langs that needed them. However, that doesn't work on multilingual projects since the lang-tags are not there for each heading individually (this is Bug 34514 ). I don't think simply setting the overflow will solve the problem if the line-height isn't set too.

Of course
#firstHeading { overflow: visible; }
doesn't prevent cutting letters entire. But it reduces the cutting.

The existing h1#firstHeading { overflow: hidden; } is not necessary and can be certainly reseted to the default h1#firstHeading { overflow: visible; } without disadvantages.

See also T333938

IMO, this task should be resolved as there are many Indic languages unless the existing line height settings are reported as being problematic for a specific language like it was for Nepali T333938. From quick testing on a few Indic wikis ta, hi, te, mr line height seems fine. Also, with the current state of Vector, is this even a valid task? cc @matmarex

I think it's valid. The problem is that the line height has been adjusted on Indic wikis, but not for multilingual wikis that contain some Indic pages. I think that fixing the subtask T36514: The language and the direction of the title in first heading should depend on page content language instead of user interface language would probably immediately resolve this task too.

The task would benefit from some updated examples and screenshots, as several of the pages used as examples in 2012 have been deleted, and you're also right that this may be less of an issue in new Vector (although headings may still be cut off with some fonts – screenshots proving this would be nice).