Is it safe to use SpaceDesk?

Question

Information Security

I recently installed SpaceDesk and it has really sped up my development - I use my laptop as another screen.
Before the installation, I had some security concerns. Therefore, I looked for reviews and it turned out that most of them are positive, and those that are less than 5 stars - something does not work for them. Something doesn't work - it didn't scare me at all. This problem is being solved. So, I decided to install this program and enjoyed using it.
However, I'm still worried about security.
First, how safe is it to use a local network for such things. Secondly, this program sees everything I do through the screen (it transmits the image from the main PC to the laptop).
And I found similar questions, although it seems to be quite appropriate and logical. Of course, I do not understand the network and to what extent the program has access to my data.
If there cannot be a clear answer here, then at least point out possible problems or something like that.
I have long had the idea to view outgoing traffic and what is leaving my computer. Just an idea. I don't even know what it will give me.