Font Rendering Bugs

James Hultquist-Todd

Spurred by Rosetta Type’s Mastodon post (https://mastodon.design/@rosetta/111652940220217980), I’ve created this thread as a repository of font rendering bugs in contemporary software. 

Go ahead and post any bugs you’ve encountered as well as any workarounds or solutions.

Font Naming Issues:
If name ID 4 (excluding Regular/Bold/Italic) is longer than 31 characters, fonts may not appear in the drop-down menu of old versions of Microsoft Word. — Viviana Monsalve

If name ID 6 is longer than 27, there can be rendering issues on Mac computers and PostScript printers. — Viviana Monsalve

If name ID 1 plus the fvar instance name has a total length of more than 31, there are weird rendering issues (most glyphs working but ligatures and substitutions being replaced by a different font!) on software that uses DirectWrite. — Viviana Monsalve

Adobe:
Adobe's Lipika engine (so when it is not using Haefbuzz) doesn't support GSUB6 (reverse contextual substitution), used for Urdu. — @Simon Cozens

Microsoft Office:
Office Software will only display the first 1,000 fonts installed on the machine.https://typedrawers.com/discussion/4834/is-the-a-limit-of-installed-fonts-powerpoint-on-macos-can-handle

PowerPoint:
IIRC PowerPoint STILL isn't enabling kerning unless its plonked in the [kern] OpenType feature. Someone please correct me if I'm wrong, as I avoid PowerPoint whenever possible. — @Paul Hanslow

Yves Michel

Is this about bugs which is something or about features missing in some softwares which is another thing (for instance, Paint Shop Pro 2023 doesn't use many OTF features)?

James Puckett

A list of unsupported OpenType features would be a list of all software that supports OpenType fonts. Nobody supports everything.

Paul Hanslow

James, add this to the list: IIRC PowerPoint STILL isn't enabling kerning unless its plonked in the [kern] OpenType feature. Someone please correct me if I'm wrong, as I avoid PowerPoint whenever possible.

John Butler

One of the IM Fell Flowers fonts crashes Scribus when you try to view it in the glyph palette.

James Hultquist-Todd

Yves Michel said:

Is this about bugs which is something or about features missing in some softwares which is another thing (for instance, Paint Shop Pro 2023 doesn't use many OTF features)?

I was thinking this would be about specific bugs that can cause issues for type designers. Those sort of bugs, as they are brought up, will be added to the first post. Feel free to add whatever you think would be relevant, it doesn’t necessarily have to fall within that scope.

Johannes Neumeier

Going through fontbakery checks and their rationales would yield a good chunk of wonky things to list, I image.

It would be nice if such a list would have grouping by features and grouping by software.

Simon Cozens

Adobe's Lipika engine (so when it is not using Haefbuzz) doesn't support GSUB6 (reverse contextual substitution), used for Urdu.

Viviana Monsalve has done extensive experiments about the length of font name IDs causing bugs in rendering. If name ID 4 (excluding Regular/Bold/Italic) is longer than 31 characters, fonts may not appear in the drop-down menu of old versions of Microsoft Word. If name ID 6 is longer than 27, there can be rendering issues on Mac computers and PostScript printers. If name ID 1 plus the fvar instance name has a total length of more than 31, there are weird rendering issues (most glyphs working but ligatures and substitutions being replaced by a different font!) on software that uses DirectWrite.

John Hudson

This should be a GitHub repo or similar, where individual issues can be properly tracked. Having a single forum thread for all the multiple issues is not a good idea.

James Hultquist-Todd

Maybe, but I’m not going to do that.