Recently faced with Read-Only button which displayed multiple times in the command ribbon of the Time entry entity.

Here is how i resolved it:

From my research, I found that the ribbon by default has Read-Only control  even without adding the control in the customization. So if you add another “Read-Only” control in the time entry entity as seen in the below screenshot, you will have duplicate buttons:

I was able to resolved the issue when i remove the read-only control from the control tab of the Time entry in the customization:

Now I got my expected result;