Created attachment 163212 [details]
A screenshot of the clock widget with a Konsole window running `watch -n 0.1 date`, the clock widget is a second behind.

SUMMARY
The Clock Widget with seconds enabled can be up to a whole second behind (see attachment).
For performance reasons I am okay if it doesn't tick *exactly* on the second, but I'd hope it to be not that noticeable (e.g. maybe it syncs up once a minute, and has a ~1000ms interval after then?)

STEPS TO REPRODUCE
1. Have the clock widget with shown seconds added somewhere
2. Load up another clock, I just used `watch -n 0.1 date`
3. Compare the clocks

OBSERVED RESULT
The clock usually doesn't tick anywhere near exactly on the second, but rather sometime after.

EXPECTED RESULT
The clock would be visually in time with any other clock on the system.

SOFTWARE/OS VERSIONS
KDE Plasma Version: 5.27.9
KDE Frameworks Version: 5.107.0
Qt Version: 5.15.10

ADDITIONAL INFORMATION
Sorry if this is a very minor issue, I just noticed it while waiting for an exam to start, and it was all I could think about.