Save Telegram chat log
tg (telegram-cli) accepts Lua scripts. Here is my script which saves as many messages as you want into a sqlite database.
https://github.com/psamim/telegram-cli-backup
I created my own script based on @Samim's in a gist.
It prints to a file so that you can save it as you like, rather than using a SQL database.
Also, it has a sleep feature so that you can a larger number of dialogs' histories. It is still limited by telegram-cli
's hard limit of 100. I changed that by editing the source and raising the limit.
Answer :
It's not possible to backup your chat history in an automated way with the official application, this feature is not provided yet
Workaround :
You can still make it manually; tested on official client on windows
- Open a chat window
- Click on the last Sent/Received message and maintain you click
- Move the mouse up to select all the messages
- Right click to copy the messages
- Save them into a text file or else