Yesterday I put Ubuntu 18.04.1 on both my Lenovo ThinkPad Yoga S1, which was coming from another distro, and on my brother's Toshiba Satelite C655, which was coming from Windows 7. The Toshiba's mouse buttons had not worked for years, so my brother always just used an external mouse with a USB Bluetooth adapter. When we put Ubuntu on it, the built-in mouse buttons still didn't work and for a few hours, the external mouse worked fine, same as it had been in Windows. But then the left-click on the mouse stopped working. Right-click still works and so does the scroll wheel. Thought maybe it was the mouse so tried a different mouse and got the same result. Restarted the computer and the mouse worked for a few minutes and then left-click stopped working again. Any idea what the problem could be and/or a possible solution?