Messages to Matrix get markdown formatted

[Mikaela]

Describe the bug

When a message is sent from e.g. XMPP or IRC that is accidentally markdown, Matrix receives the message markdownified. This is especially distruptive when sending code or links that happen to contain underscores.

To Reproduce

Demo instance: Send a message beginning with # on https://t.me/Matterbridge and watch it become a <h1> on #matterbridge:matrix.org.

Expected behavior

I expect the message to leave and arrive as plaintext without getting strangely interpreted as markdown making the message difficult to read.

Screenshots/debug logs

Debug log: not applicable

Environment (please complete the following information):

• OS: Debian GNU/Linux 9.12 (stretch)
• Matterbridge version: 1.16.5 4be00bb

Additional context

Config file has two IRC networks, one Matrix server, one XMPP server and

[general]
RemoteNickFormat="[{LABEL}] <{NICK}> "
IgnoreFailureOnStart=false
MessageSplit=true

more information available on request, but the configuration or gateways don't seem relevant as I can reproduce this on the support group/room matterbridge.

[qaisjp]

If you sent a message starting with # as a normal user on Matrix, would it render as a <h1>? If so, then imo I this should be kept as default behaviour with "no-markdown-rendering" kept behind a setting.

i.e. imo someone on IRC saying One **two** three four should render on other Markdown-supporting platforms as "One two three four"

[Mikaela]

If you sent a message starting with # as a normal user on Matrix, would it render as a <h1>?

Yes and if I send

testing https://www.reddit.com/r/gaming/comments/fcvmfo/can_we_all_agree_the_tiger_knee_position_is_the/ top of /r/all

it will be

testing https://www.reddit.com/r/gaming/comments/fcvmfo/can_we_all_agree_the_tiger_knee_position_is_the/ top of /r/all

but if it's send through matterbridge it's suddenly

testing https://www.reddit.com/r/gaming/comments/fcvmfo/canweallagreethetigerkneepositionis_the/ top of /r/all

Reddit is a bid bad example as it recognises that ID fcvmfo causing the link to still work, but I imagine it would break in many other situations.

---

Edit: a better example is Test including Wikipedia's article of the day with a heading with multiworded subtitle: https://en.wikipedia.org/wiki/Tourette_syndrome#Psychoeducation_and_social_support which Matterbridge turns into

which file redirecting to the correct page, loses the anchor information. The preview below suffers the same issue.

[42wim]

@Mikaela your last issue with the underscores is already fixed in master a while ago.
Could you run matterbridge dev build? https://bintray.com/beta/#/42wim/nightly/Matterbridge/v1.16.5-30-g6b4b191?tab=files

[42wim]

@Mikaela or run v1.17.0 which is now out

[Mikaela]

Sorry, I missed your previous comment 9 days ago, but yes, link handling seems to now be fixed. Thank you 💜

I still wish I could disable the rest of the markdown though.

[Mikaela]

Some issues I have noticed today and that have caused headscratching:

• XMPP sending e.g. </sarcasm> to Matrix results an empty message unless the Matrix user looks into message source.
• Sending a list of things to do from IRC:

1. have more caffeine
2. do something
3. do something more

results into Matrix having everything labeled as 1. as matterbridge converts plaintext-IRC to markdown unexpectedly. I imagine there are other scenarios where this confusion arises from incorrectly formatted messages.

[Mikaela]

Mathematics from Telegram to Matrix are also interesting.

[42wim]

HTMLDisable option is now available in master.

[bkil]

Thanks for the feature. I wanted to enable just this, but I've ran into an issue:

• HTMLDisable for Matrix adds empty format and formatted_body fields #1382 HTMLDisable for Matrix adds empty format and formatted_body fields