Never seen that problem during over 20 years on Macbooks.
How to fix that? Cannot find a way to update or reinstall the Activity Monitor app.
Running MacOS Catalina 10.15.5 on MacBook Pro (13-inch, 2017).
They are there however may be moved (and hidden) to the extreme right. Open Activity Monitor and widen the window to the right until you see at least one column. Drag that column to the Left and the other related columns should follow..
Axel F.
You are right - many thanks for the tip. Problem solved.
Strange that the 'Process' column suddenly expanded to show up so hugely wide as it did, without any change from my side.
You are welcome.
Axel F.
Activity Monitor suddenly not showing the columns under the headings.
