Allow Backfill feature in Telegram

[Tycho-S]

Is your feature request related to a problem? Please describe.

It's not a problem as such. It would just be really great to have.

Describe the solution you'd like

Right now the bot only backfills a handful of messages. But you can set backfilling to complete in mautrix-telegram. It's just that the ansible playbook doesn't offer these options yet. It would be great to have a setting in the playbook that sets the backfilling to unlimited.

Describe alternatives you've considered Modifying the conf file by hand, but it gets overwritten every time I update.

Additional context The required settings are in this example config file, under bridge and then backfill: https://github.com/mautrix/telegram/blob/b5c294a558b8536e93a9cb89b46f57958d1554e0/mautrix_telegram/example-config.yaml#L402

[aaronraimist]

@Tycho-S You can configure any configuration options you want by putting matrix_mautrix_telegram_configuration_extension_yaml into your vars.yml file.

Example: https://github.com/spantaleev/matrix-docker-ansible-deploy/blob/16233354cbfa24b4401902bbe49dbf7705f10293/docs/configuring-playbook-bridge-mautrix-telegram.md#usage

[chuckwagoncomputing]

I have only been able to get Telegram backfilling to work properly by disabling MSC2716. The telegram bridge then uses timestamp massaging instead. However, the current release of the whatsapp bridge doesn't support that yet (it seems to be on the way), so you have to disable backfilling on the whatsapp bridge.

[starascendin]

@chuckwagoncomputing could you kindly share how you got telegram backfilling to work? I am in the process of configuring the bridge, and am quite clueless on how to do it with this playbook