v27 and v28 editing areas slow down

[iccpicc]

I used the v26 version of the editing area to run smoothly, with the mouse scroll can respond immediately;
The v27 v28 version also responds smoothly when the file is first opened, but after a few minutes, the response will become slow and stuttering, and the mouse will not be able to move immediately after scrolling.
But if you reload the file again, the reload_with_encoding command gets faster again, for some reason;
I also checked that the Settings for option--File Options--Load are the same as in V26, but they are not resolved.

[Dan]

If you're using Git, you could make sure Live Diff is off. But I don't notice it slowing things down and still use the editor every day.

[iccpicc]

I don't use git, all my code is on local disk, are there any options that might affect this? Such as time Settings.