That would be opening a can of worms!
What do you mean?
If a situation is described as being a can of worms, it is much
more complicated than it seems. If someone says, "that would be opening a can of worms." they mean that doing something would lead
to all sorts of complicated problems, and that it would be better to leave
things as they are.
"I wanted to find out why the video wouldn't work on the usual
setting, but Dad said to leave the TV as it was. He said it would
be opening a can of worms if we started changing the channels."