Starting gateway failed: Bridge failed to start: unsupported mattermost version

[mstyp]

Describe the bug

I can not bridge to a mattermost 6.* instance, getting a "Unsupported mattermost version" error, which looks like it should have been fixed upstream but maybe has not been fixed here: 42wim/matterbridge#1606

Context

• Hardware: *VPS bought online / Old laptop or computer / Raspberry Pi at home" (all of these fail)
• YunoHost version: stable and beta.
• I have access to my server: Through SSH | through the webadmin | direct access via keyboard / screen | ...
• Are you in a special context or did you perform some particular tweaking on your YunoHost instance?: no

Steps to reproduce

config matterbridge .toml with the following:

#[mattermost]
[mattermost.BLANK]
    Server="BLA-NK.BLANK.BLANK" 
#this server uses sub-domain with a dash in it, EG one-two.three.com or sub-domain.website.net)
    Team="BLANK"
    Login="BLANK"
    Password="BLANK"
    PrefixMessagesWithNick=true
#    RemoteNickFormat="[{PROTOCOL}] <{NICK}> "
    RemoteNickFormat="{NICK}   "

[matrix.mymatrix]
(matrix gateway configs, etc etc)

[[gateway]]
name="BLANK off topic"
enable=true
    [[gateway.inout]]
    account="matrix.mymatrix"
    channel="!gibberish:mylocalmatrix.local"

    [[gateway.inout]]
    account="mattermost.BLANK"
    channel="off-topic"

Expected behavior

Should connect to mattermost.

Logs

level=info msg="Starting bridge: mattermost.BLANK " prefix=router
level=info msg="Connecting using login/password (sending and receiving)" prefix=mattermost
level=info msg="Using mattermost v6 methods: false" prefix=mattermost
level=info msg="Connecting BLANK (team: BLANK) on BLANK" prefix=mattermost
level=fatal msg="Starting gateway failed: Bridge BLANK failed to start: unsupported mattermost version: " prefix=main

The mattermost server version is 6+,.

[mstyp]

I'm still having connection issues but I think unrelated to "unsupported mattermost version". I added a flag v6=true flag and that seems to have worked (even though thats supposed to be unnessisary), and now the latest debug message is Connecting BLANK (team: BLANK) on BLA-NK.BLANK.BLANK:443 rather then just a failure message,

But none of the messages back and forth are being bridged. It detects when I send a message from my local matrix instence but it never sends to mattermost.

unsure what next steps are. If somone wants to close this issue thats fine with me, otherwise will keep open till i fix whatever problem it is I'm having.