Network manager editing error

Hi everyone.

I'm using Ubuntu Mate 20.04 and I have problem with my Network manager.

When I'm editing the IP address in the network manager as the administrator user, the cursor would only stay in the address bar for no more than 2 seconds. For example, if I want to type in 192.168.1.2 in the IP address bar, I would click on the address bar first then type in something like "192." and the cursor would disappear after 2 seconds, I had to click on the address bar again then continue type in something like "168."and the cursor would disappear after another 2 seconds...

It's really torturing me now as I need to click and edit at the same time every 2 seconds! I already reinstalled the network-manager but it won't help.

The interesting thing is that I don't have this problem on terminal or elsewhere. I don't have this problem with my desktop user either. Even when I login to the pc via vnc viewer as the administrator user I can edit the IP address with network manager without a problem, the cursor stays in the IP address bar forever. Maybe this has something to do with the desktop file? I don't know.

This might not be a common issue as it's not a big issue at all. Any one might have an idea how to deal with this? Thanks!

I found a workaround here by launching the network manager from terminal as root:

$sudo nm-connection-editor

In this way the cursor would stay there forever.