This can happen because of two different problems. The mouse left click switch may be glitching which means a repair or replacement is due. The double click speed may be set too slow causing a mouse click a second later to be interpreted as a double click which opens the PiP Designer. You can check and adjust the double click speed in the windows control panel for the mouse and set it to your liking.

This doesn't help if the mouse click switch is intermittently glitching causing a double click when you only clicked once.

Quote I place a clip on the time line and select it to move. The hand shows up , but when I click on the mouse it turns into an arrow goes into the PIP screen which is a pain. this happens often. How can this be avoided?

It sounds like the microswitch in your mouse is going bad. That's a thing that happens, and is why I don't buy $100 mouses. They're all prone to it. As your mouse continues to degrade, it will start sending more and more "click" pulses at a very rapid rate. It will eventually become so bad you can't tolerate it anymore, because you won't be able to drag screen objects.

Find a cheap gaming mouse that doesn't have a lot of bells and whistles. I like Redragon. They have a high DPI and a sturdy and comfortable enclosure, but don't cost too much.

Quote It sounds like the microswitch in your mouse is going bad. That's a thing that happens, and is why I don't buy $100 mouses. They're all prone to it. As your mouse continues to degrade, it will start sending more and more "click" pulses at a very rapid rate. It will eventually become so bad you can't tolerate it anymore, because you won't be able to drag screen objects.

Transigence - How very true it is. Let’s hope that the OP replaced the mouse and continued editing. I recalled the time I purchased a replacement microsoft brand mouse that started glitching after 2 months of heavy video editing. There are the switch debounce software that can provide a temporary fix. Did not want to buy a new mouse every two months so I looked up solutions found on the internet and applied it. I am using the same mouse for the last 10 years with no problems now.

Let the wealthy editors buy a new mouse every two month to keep the mouse manufacturing line going. Lol