Changing Telegram Account's easily from the Lock Screen on Desktop Devices would be nice. This would solve some issues like:
Shared devices: Sometimes many people uses the same device to text and communicate with friends or even work. (I know Telegram already has an option to add a second account, but for that would need the other person password to open Telegram from Lock Screen , and unfortunately all that person private chats would be exposed to this other person that's trying to sing in on their account. (Where a solution should be this, that I've suggested 300x in here. Dedicated password and Biometrics to access Sav... #23028 , Enable Fingerprint and PIN locker to individual... #5454 and this other suggestion is brilliant too Emergency passcode to hide chats #2775).
The new layout of Telegram Lock Screen would be like a regular sign in page. Where the profile pic of the person would be in The middle of the page and above the password text box, The profile icon in the left side of the password box, to select another account to sign in or log in and in the right side of the password text box, is the usual "confirm/enter" button.
If there's an account yet vacated to be Signed in and it's the first time it's been signed in on the device, would need to athenticate as usual with Telegram's cloud password, sms confirmation,etc.
Would be possible to add at least 4 to 6 accounts and keep them "Signed in" on the computer. (Won't need to use the Telegram cloud password again to log in when switched between these profiles already "sign in" on this device).
About the usage of storage on the device, by standard all the cache of all acounts would be resctricted to the basic option offered by telegram, minimum 5Gb up to 16Gb. (Having more than 2 telegram account's would drain the storage of the device really fast, if all accounts cache get untill 5Gb or the maximum 16gb set in settings by one of the accounts, all the cache would be cleaned up!
For matters of Privacy, the account with the profile active in the locker screen would be the account "activated"/ in use right at that moment. Which means, just this account would be notifying messages at that moment on that divece and not the other accounts. To access each account, each user will need obligately to set a passcode/password as already been done with one single account. (When need to leave from the device for a while, the user just tap in the padlock as it has on the mobile devices (would appear now in the menu bar of telegram's desktop too)or just use the shortcut as in MacOS [command + L] to just lock your account back.
When another user wants to log in his account, tapping the left icon profile, would list all the accounts already signed in with the small profile pic and their account name. If there's a vacancy to sign in one more account would show a plus sign to sign in the new account( and this process would be the usual sign in scheme of Telegram). If the selection was one of the already signed in accounts the user just would need to type his passcode, and that time just his account would be shown notifications of their contacts on the device, not of the other accounts.
Second step to increase security and privacy, it's when user want to log in his account, a message on the mobile telegram would appear showing him that someone is log in on some device (like it's done here to log in, showing a short notification asking to confirm or decline this request). But to this one would just show the option to decline, once the device would be considered reliable as it's already sign in with telegram's cloud password authentication. The decline button would be useful if someone could somehow to discover the passcode to access the account, giving the user control over the access of his account. (When the person tap decline, the entire account would be shut down from the device, needing again to authenticate on this device all over again with 2AF password). Would be kinda of the function of the "KILL SWITCH" button!