Keyboard and trackpad freezes on macbook pro

I want to share a solution to this - I'd tried everything - PRAM, NVRAM, disc checks on recovery mode, installing Mojave, deleting SSD images during hibernation....

Still get the cursor freezing on bootup. So frustrating...

Now I have finally found the answer - it's hardware-related, but you might not need to replace anything.

Just press the bottom of the macbook case in the middle during bootup.

That's it!

It seems to apply just enough pressure internally to make the connection on the keyboard ribbon. Crazy eh?