When you import chat history into a chat from other apps, imported messages will be sorted by original sending date and merged with existing messages in:
Newly created 1-on-1 and group chats.
Any existing 1-on-1 chats that have fewer than 1000 messages (on Telegram).
Smaller existing group chats with basic settings that have fewer than 1000 messages (on Telegram).
Unfortunately, it is not possible to merge existing and imported message histores in chats which have more than 1000 messages and in large groups (or groups with altered settings: e.g., with "message history" set to visible for new members, etc.)
In the cases when it's not possible to merge histories, imported messages are placed into the moment when they were imported. All messages include their original timestamps and follow one another in the correct order.
Workaround
To make it easier to navigate chats where merging is not possible, you can pin the last message in the chat before you import messages. This way you can quickly jump past the imported messages if you need something above them.
There is a problem with certain guys who are already in group too. In this case Telegram just shows their names or phone numbers like they are in WA export file without connection to Telegram id. As a result no photo and link to such contact.
Hmmm exploring the import feature even more, it also happened here. And some numbers that have Telegram and are in the group, only had their profile linked in the first messages, in the old messages don't have the link, only the contact phone number. I don't know if it takes Telegram a while to link everything.
Антон
Has anyone already figured out how to solve profile linking problem?
Lucas Dondo
Hello, today I had this issue importing a WhatsApp chat to the existing Telegram one because for a few days I had no more option than to use WhatsApp 😒 with this person (and we don't want to loose those chats). Hopefully I found this, which gave me hope, but I don't understand why does this issue have the "Fixed" tag.
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