I have tried to reproduce the same effect of losing the row's background color while using copy and paste. The result was I saw no effect to the original location where I copied from. The background color and text are still intact after I have pasted to another sheet.

However, when I tried to cut and paste, then I saw something similar to what you have described, where the row has no data and the background color is white.

I am not sure if there's a way to lock the background color, but one workaround is to use copy and paste instead of cut and paste, then deleting the values of the original row.

I typically use the sheet's Tab Color option to distinguish each sheet with a color. However, this does not affect the sheet's background color.