Sign

[Eren180899]

What's this timer kind of sign to the left of Bluetooth?

[Delhi_se_hu_BC · Accepted solution]

I think you were using the maximum or high processing speed that's why it's show like clock.
You can turn off by choosing optimized option.
Accept as a solution if that's work.

[URWASEEMKHAN · Accepted solution]

To turn the setting off go into Settings> Device care> battery> power mode and toggle to what power mode you desire. 

[unknown_s · Accepted solution]

It is The Symbol Of Performance Optimization

[unknown_s]

Performance optimization Means the process of modifying a system to amplify its functionality, thus making it more efficient and effective.
You Can Turn It Off By The Following Steps:-
Open Setting→Device Care→Battery→Processing Speed→Change It To Optimised Option.
If You Consider It As Helpful Please Make It A Sollution.