Nodes fold up and links disappear in material editor


UE4.7.5 & 4.7.6 - Nodes disappear in material editor.

I have spent a long time making a landscape and have just got to the point where I apply the material. A couple of days ago (4.7.5), in the material editor, I was trying to pick up a wire from a link and it wouldn’t pick up. It took about 5 attempts to get the wire. When I tried connecting it to another node, EVERY node in the material ‘folded up’. I unfolded the texcoord node with the little white arrow but the link connector had disappeared completely (see pic). I turned off the editor and shut down the pc thinking it was a minor bug. Today (4.7.6) I opened up the material again to find all the nodes still folded and with missing link connections. I can’t connect anything together.

Has anybody else experienced this and if so is there a fix available, because I don’t want to lose all my work?

Thanks in advance x.

I’d just like to add that the more I play with the nodes the more connectors disappear and my material becomes useless. I have also spent a lot of time on the material so I would hate to have to lose that and start again.
When I open the material, any nodes connected together still show the connectors, but if I disconnect a wire, the node connector also disappears.
Look at the Texture Sample, the red, blue and alpha connectors have all disappeared.

Copying all and pasting in a new material doesn’t fix anything. All my materials are behaving in the same way.

If I break a link, the connector disappears but I can undo to get the original connection back.

EDIT I found out how to fix this ‘problem’. There is a button at the top of the material menu called Connectors. I must have accidentally clicked it at some point.

Thank you for all the help.

Thank you!