v5.15.2.1
Official changelog:
- Send Direct Messages to Channels.
- Enable New Tab Layout for Topics.
- Create Polls with Up To 12 Options.
- Add statistics for user stars.

v5.16.0.1
- Improved voice messages bitrate (32 to 128)
- Removed delay when recording voice messages
- Reduced chat preview delay
Official changelog:
- Create private and group checklists.
- Suggest Posts in Channels.
- Monetizing via Suggested Posts.

v5.16.1.1
Official changelog:
- Fix inline keyboard updating in bot messages.
- Fix possible crash in fast chat switching.
- Different minor fixes.

v5.16.4.1
- Show more info for unique gifts
- 256 bitrate in voice messages
- Hide phone number for non-contacts in top bar
Official changelog:
- Allow removing / charging fee in channel direct messages.
- Don't offer creating checklists in channels.
- Support author channel in gifts.

v5.16.6.1
Official changelog:
- Age verification support.

i don't know why they didn't mention in the changelog that this update adds gift collections in profiles and support for purchasing new (not yet released) gifts
group calls have also been fixed

v6.0.0.1
Official changelog:
- Public Post Search.
- Story Albums.
- Gift Collections.
- Profile Rating.

v6.1.0.1
Official changelog:
- Music on Profiles.
- Gift Themes.
- Gift Value Information.
- Upgrading Gifts for Other Users.

v6.2.2.1
Official changelog:
- Comments and reactions in group calls.
- Notes for contacts.
- Suggested birthdays.
- Threads for AI bots.
- Reorder gifts collections and stories albums.
- Reorder gifts inside collections.
- Apply tags instantly when forwarding to Saved Messages.
- Choose which screen to show notifications on.
- Nice text message sending animation.

v6.2.3.1
Official changelog:
- Fix crash when viewing messages with hidden senders.
- Fix possible crash when editing contacts.
- Fix layout of character count warning in contact notes.
- Fix icons when editing contacts.
- Fix color of sending messages animation in complex themes.
- Fix crash in chat open on Flatpak build.

v6.4.0.1
- Enhance platform detection for photos
Official changelog:
- AI Summaries for posts in channels.
- Show who sent your unique collectible gifts.
- Offer stars or TON for unique gifts.
- Support passkey login on Windows.
- Export separate topics message history.
- Export audio files saved to profile.
- Reorder stories in stories albums in My Profile.
- Add your Saved Music to data export.
- Reorder saved music in My Profile.
- Support for Gift auctions.
- Support for Live stories.
- New profile pages design.
- Highlight links in contact notes.
- Show menu with screen share controls in wide group call mode.
- Fix possible crash in saved music removing.
- Fix crash in theme editor.