A lot of promotion arrives not as plain text but as a forwarded post, a message from another channel, or something sent through an inline bot. Telm has a master external-promotion filter that blocks all of these at once — forwards, channel posts, via-bot messages and mentions or links to outside channels and bots — while always allowing the automatic posts from your own linked channel. A whitelist lets you permit the specific channels you actually trust.
Want to set this up? Do it right in your Telm account.
Open in your dashboard1How promotion sneaks in
Spammers rarely type an advert as plain text anymore. Instead they forward a promotional post, post as an anonymous channel, or use an inline bot to inject a message. Each one carries a link to somewhere else — the whole point is to pull your members out to a third-party channel.
Blocking one route is not enough, because the others stay open. Telm handles the whole category with a single switch.
2The external-promotion filter
The external-promotion filter is the master control. When it is on, Telm removes any message whose purpose is to push an outside channel or bot, no matter how it arrived.
- Forwarded messages (except the automatic posts of your own linked channel).
- Posts sent on behalf of another channel (anonymous channel senders).
- Messages injected through an inline bot.
- Mentions of, or links to, third-party channels and bots.
3Allowing the channels you trust
You rarely want to block absolutely everything. The whitelist lets you name the channels and bots that are welcome — a partner project, your own network of communities, a bot your group relies on.
The logic is deliberately safe: with an empty whitelist every external reference is blocked. Once you add entries, a message is allowed only if every channel or bot it references is on the list; a single unlisted reference means the message is removed.
- Empty whitelist — block all external promotion (the default).
- With entries — allow a message only if all of its references are whitelisted.
- A reference that cannot be resolved is treated as not allowed.
4Blunt filters for stricter groups
Alongside the smart external-promotion filter, Telm offers plain on/off filters for whole categories of content. Use these when a category has no place in your group at all, not just its promotional use.
- Block all forwards — delete every forwarded message, promotional or not.
- Block channel posts — remove messages sent as anonymous channels.
- Block inline bots — remove anything injected via a bot.
- Block stories — remove reposted stories.
5Your own linked channel is always fine
If your group is the discussion chat attached to a channel, Telegram automatically forwards each new channel post into the group. Telm recognises these automatic posts as your own content and never treats them as external promotion — even with the strictest settings on.
So you can lock down outside promotion completely without accidentally deleting your own announcements.