Tdesktop: [Regression] U+2661 renders incorrectly in 2.1.5; works fine in 2.1.4

[Zenexer]

Steps to reproduce

1. Attempt to send or receive character U+2661 (♡)

Expected behaviour

Should appear as a black-and-white (non-emoji) heart:

Actual behaviour

A character containing three vertical lines appears instead:

Configuration

Operating system: Windows 10, up-to-date

Version of Telegram Desktop: v2.1.5 (beta); can't reproduce in 2.1.4

Used theme: Default; happens in both normal and night mode

[Zenexer]

Per https://t.me/TelegramDesktopTalk/36813, U+2661 (♡) appears to render as U+2261 (≡). U+2261 renders as expected.

[vimpostor]

Cannot reproduce on Telegram 2.1.6 on Linux linked to Qt 5.14

[Zenexer]

It may be limited to Windows. Someone reported it in https://t.me/TelegramDesktopTalk, and I was able to reproduce it; we were both on Windows 10.

[Zenexer]

I'm still able to repro it on 2.1.6.

[Zenexer]

Still able to repro in 2.1.10, currently no workaround.

[stale[bot]]

Hey there!

This issue will be automatically closed in 7 days if there would be no activity. We therefore assume that the user has lost interest or resolved the problem on their own.

Don't worry though; if this is an error, let us know with a comment and we'll be happy to reopen the issue.

Thanks!

[Zenexer]

Anyone know if this is resolved? I don't have access to TDesktop at the moment.

[ilya-fedin]

Anyone know if this is resolved?

This won't be solved since this issue is on Qt level. 2.1.4 was the one version that displayed this character due to the fonts experiments, current behavior is the right and won't be changed.

[Zenexer]

Thanks, @ilya-fedin. We've been getting people asking about the issue in https://t.me/TelegramDesktopTalk. Do you happen to have a link to the Qt issue to which we can point them?

[Zenexer]

Debug note: switching between FreeType and GDI doesn't fix the issue.

[ilya-fedin]

This is not a Qt issue, this is a Tahoma issue.

[Zenexer]

Thanks, that explains it. I can confirm that the glyph in Tahoma is wrong, and I'm assuming that TDesktop falls back to that since Open Sans lacks a glyph for U+2661. Case closed.