Double images when pasting with Ctrl-V -- starting in the last 2 weeks

When copying an image from another program, such as Snagit or powerpoint into gmail using firefox, I get two identical copies of the image. When copying formatted text from Powerpoint to gmail, the text also shows up twice -- once with the formatting, and once without the special formatting. However, when copying text from Word to gmail, the text only shows up once -- with the formatting. This does not happen with Chrome. It does not happen when copying the image or text into another microsoft program like word. It only happens in Firefox. I have refreshed Firefox, disabled add-ins, and cleared cache. Nothing helps. Please advise on how to stop this from happening when copying an image or formatted text. This problem has only started in the last couple of weeks. I am using Firefox Version 87.0 Build ID 20210318103112 with Windows 10.