Resize an image by percentage?

I was trying to resize an image by percent but can’t find any way. Another post gave this solution:

Right-click the image. Find the item “Crop Picture” in this context menu. The dialog has a part “Scale”, where you can enter a percentage. Make sure to use the same value for width and height for to keep ratio.

But I simply can’t find the dialog and Scale.
This is the only thing I see - just the blue corners.

Does anyone know how to resize by percentage?

Somehow the default setting didn’t have crop dialog button. So if I go to customize and add that, then the dialog button appears!

But I also noticed that even the lock size ratio is selected, when resizing it by percentage (crop dialog), the ratio is not locked.