[NEW] KaTeX Support

[jGleitz]

Rocket.Chat supports posting KaTeX, which will get rendered nicely in the conversation. For us, this is an outstanding feature.

Unfortunately, when posting KaTeX in the native app (e.g. $x$ or \[x\]), it is not rendered as KaTeX but stays as it is.

[matheusjardimb]

Hello @jGleitz, thanks for submitting issues!

This seems to be a good feature request 👍

[markbolo2]

Any progress on this? Reading chat on the mobile is super ugly because of all the Katex formatting that is not coming over.

[rafaelks]

@markbolo2 Do you have any idea how this could be implemented?

[wreiske]

Ahh! Please add support for KaTeX on the Android mobile app!

Desktop:

iOS

Android

https://apis.reiske.tech/math

[naidu]

Does anybody monitors this space? No comments from the owners of the product.. :(

[rafaelks]

@naidu Yes, we monitor this all the time... PR are welcome for this issue! Thank you! 👍

[vasylnakvasiuk]

Is this codebase for RocketChat Experimental or basic version?

[rafaelks]

No, this is the native version from Play Store.

[blindrain]

This is still an issue with Android and Windows applications.

[edmundlaugasson]

This is still an issue with Android and Windows applications.

Not only, also GNU/Linux app is affected.

[diegolmello]

Hey, I transferred this issue to the new repo.

[raffaeler]

Is this feature working on any client? I can't make it work on any client (web, desktop and android)
TIA

[phriedrich]

@raffaeler Yes, it's working for me in the web version. (It has to be enabled in the settings under messages.)

But it's not supported in the mobile app.

[raffaeler]

thank you @phriedrich. The option is enabled in Messages but I can't make it work from the web.
Could you please type here an example so that I am not misunderstanding the KaTex syntax?
Thank you

[phriedrich]

The example up in this thread here works for me with the same syntax:

But it's also possible to set the syntax from \[KaTeX Block\] to $$KaTeX Block$$:

If you can't get KaTeX working at all, this is probably more a question for Rocket.Chat itself, and not for the mobile app.

[raffaeler]

Thanks but the syntax with the square bracked does not work.
I enabled the Dollar syntax and it works.
The strange thing is that when I enable the Dollar syntax the square bracket syntax gets swallowed.

It may be a bug. I am using version 3.2.2

[kdev]

Upvoting this for implementation

[no-trick-pony]

I am a bit confused: Why would you implement this and display it in the UI directly below the chat input at the same level as bold, italic or inline code when it is basically broken in all of your own mobile clients?

[johncrisp]

Hi,

So the situation here is complex.

First thing to note is that the mobile app is not 'broken'. However, the specific functionality you require is not yet implemented.

It's not implemented because Katex uses web stuff to render the math operations.

As a result we'd need to either create a native module to do that, or try to embed a webview into the message component.

It is on our long term road map to look at this, but it is not at top of the list for priority right now I'm afraid.

I'll leave this issue open accordingly.

Thanks.

[66Leo66]

As a result we'd need to either create a native module to do that, or try to embed a webview into the message component.

There's modules that could render KaTeX without using webview but svg instead. Check https://www.npmjs.com/package/react-native-math-view

By the way, as this issue causes a mess on native clients when reading messages with KaTeX, why is it "not at top of the list for priority right now "?

Looking forward to a fix!

[ankar84]

Still not implemented in latest Rocket chat React Native mobile app
Web client

Mobile client

[ankar84]

@GleidsonDaniel hey!
Strange, but looks like Katex still not supported in new 4.29 version
Mobile cleint 4.29.0.34197 (iOS)

Web client

Or it will be implemented in next 4.30 release?

[diegolmello]

Possibly related to RocketChat/fuselage#775?

[dnlsilva]

It's working, you're probably just using an outdated version, given that PR was merged 16 hours ago and version 4.29.0.34197 came out 3 days ago :)

Yes, it will be available in the next version.

[pegonma]

I am using the RocketChat Android app (version 4.35.1.37443) and latex formulas are not rendered on the map (neither with the syntex ( ) nor with [ ]). While it is rendered on the web app, so this does not seem to a problem with the setting of our server (provided by our university).

@GleidsonDaniel I am confused, which app/device are you using?

(My server is chat.univ-lille.fr and the server version is 3.15.2).

[dnlsilva]

I am using the RocketChat Android app (version 4.35.1.37443) and latex formulas are not rendered on the map (neither with the syntex ( ) nor with [ ]). While it is rendered on the web app, so this does not seem to a problem with the setting of our server (provided by our university).

@GleidsonDaniel I am confused, which app/device are you using?

(My server is chat.univ-lille.fr and the server version is 3.15.2).

@pegonma the problem in your cause is probably your server version.

[pegonma]

@GleidsonDaniel Is it really possible? That the server allows the desktop client to render KaTeX formulas but not the mobile app? Can you tell me what is the latest server version? So I can ask the IT of my uni to update it.

[dnlsilva]

@GleidsonDaniel Is it really possible? That the server allows the desktop client to render KaTeX formulas but not the mobile app? Can you tell me what is the latest server version? So I can ask the IT of my uni to update it.

@pegonma After version 5.0 of the server we changed the way messages are rendered and tagged and in this version we added support for katex.
Before that the app never had katex support.

So, as I said, to work katex in the mobile app you must have a server running above version 5.0 and as your server is in version 3.15.2 it will not work.

[pegonma]

@GleidsonDaniel thank you very much for your answer!