I am using Everything on two computers.
On my home computer (still running Windows 10) all text file previews are instant.
On my work computer running Windows 11 some are instant (ex. .csv) but some (ex. .txt) are very slow and showing a "Loading..." bar regardless of size.
It might be your preview handler for txt files.
Do csv files look different to txt files in the preview pane?
Does the issue occur in Windows Explorer?
Please make sure Everything is installed correctly and running as a standard user:
In Everything, from the Tools menu, click Options.
Click the General tab on the left.
Check Store settings and data in %APPDATA%\Everything.
Uncheck Run as administrator.
Check Everything Service. (Please make sure this is tick-checked and not square-checked)
Click OK.
Exit Everything (right click the Everything tray icon and click Exit).
Restart Everything.
Please try overriding your txt preview handler in Everything:
In Everything 1.5, from the Tools menu, click Options.
Click the Advanced tab on the left.
To the right of Show settings containing, search for: preview
Select preview_handlers.
Set the value to:
[{"filter":"*.txt","handler":"{1531d583-8375-4d3f-b5fb-d23bbd169f22}"}]