Sailfish Browser cannot display all characters of Old Bulgarian

[ddobrev]

REPRODUCIBILITY (% or how often): 100%
BUILD ID = OS VERSION (Settings > About product): 4.0.1.48
HARDWARE (XA2, Xperia 10…): Xperia 10 Dual SIM
UI LANGUAGE: German
REGRESSION: (compared to previous public release: Yes, No, ?): ?

DESCRIPTION:

Some characters of Old Bulgarian aren’t displayed in your browser.

PRECONDITIONS:

A connection to the Internet.

STEPS TO REPRODUCE:

1. Open Словѣньскъ ѩꙁꙑкъ · Википєдїꙗ

EXPECTED RESULT:

All characters are displayed.

ACTUAL RESULT:

Some characters, such as “ꙁ” in “ѩꙁꙑкъ”, are displayed as black boxes.

ADDITIONAL INFORMATION:

Firefox, which shares the same engine, displays all characters at least on macOS. I haven’t tested recently on other OS-es, desktop or mobile.

[deloptes]

it is not about firefox - can you check what encoding is used on the Mac?
Hier on linux with firefox it does not display all characters. The site you linked says it is UTF-8, so probably we are missing some specific font.

[ddobrev]

I cannot tell, I’m afraid. “Text Encoding” is disabled (greyed out) in my Firefox, and Safari, which also displays all characters, says “Standard”. My Firefox (87.0) on Kubuntu 20.04 with full updates also displays all characters but it too has the menu disabled.
I tend to agree it might be a missing font. Many applications, possibly Sailfish Browser as well, have the ability to fall back to other fonts for particular characters. This is a bug report I sent to Firefox for windows 5 years ago where they state the same.

[deloptes]

Here it is debian 10 and FF 82 and it does not show up properly

I just want to say it could be more specific linux problem

[ddobrev]

Thank you for looking into it. There’s unfortunately nothing more I can do to help except recommending reading the linked bug report for Firefox in more details. There are screen-shots, details about the missing character, linked fonts for Old Bulgarian, notes about the behaviour on other systems, etc. I believe some of the information might help find a fix.

[dumol]

Looks like you’re missing the required fonts. Download a font with good coverage for Old Bulgarian and copy it to $HOME/.local/share/fonts/.

Here’s a screenshot of how that Wikipedia page looks for me (not ideal, but I’m not into Old Bulgarian): https://imgur.com/a/i9e31c8

[ddobrev]

Thank you for helping out. I tried 2 fonts that claim to have all characters but there was no difference. Could you please point me to the one you know works?

[attah]

Judging by the pixelated nature of those characters, i assumed it is GNU Unifont, and indeed that makes it work for me.

[ddobrev]

This font works which means so does the approach. Thank you. Now it’s just a matter of finding a font I like.
@deloptes please consider this fixed.

[ddobrev]

Actually, there’s something to fix. You could deploy a font for Old Bulgarian in the system, so users won’t have to install anything. I found Shafarik from https://sci.ponomar.net/fonts.html which you can see uses SIL Open Font License, version 1.1 that I assume is permissive enough. The result looks like this:

The character of “ꙁ” is needlessly bold but still much better than the jagged font shown above and definitely way better than square boxes. Combined with the free licence, I think you can safely include it in the system itself.

[dumol]

Just a friendly question… Old Bulgarian, also known as Old Church Slavonic, is a dead language, as far as I know. Why would you want this supported on a modern mobile device?

Mobile devices have various memory constraints (RAM, disk, etc.), so it’s not currently feasible to properly render all the languages of the world, never mind the dead ones like Old Bulgarian or Gothic.

However, I hope this would be the case sometime in the future. I, myself, am currently working on a related project, which also happens to improve the situation on Sailfish OS in regard to supporting Old Bulgarian. Please try High DPI setup. by dumol · Pull Request #10 · dumol/PixelPerfect · GitHub and let me know… Thanks!

A proof from my XA2 phone with Sailfish OS: