So once in a while I get these days on my Dell G5 running Windows 10 where the spacebar decides to hold itself down (without any physical holding down). ex:       t          h  i s                 i s     h e    l  l 

I use the laptop screen and an external monitor + an external mouse and keyboard. So I don't use the laptop's keyboard often. 
The spacebar starting its fit usually is preceded by the backlight of the laptop's keyboard turning on and then presses spacebar until I press fn+f7 which then stops it for a couple of minutes.

I have :

• uninstalled and reinstalled several times the keyboard and mouse drivers
• restarted the device a bunch of times
• entered safe mode and fixed all corrupted files
• cleaned the laptop's keyboard
• turned off the trackpad of the keyboard
• used the native troubleshooting feature, the supportassist test, the windows device tests and a bitdefender scan (all ok)
• disconnected all peripherals 
• checked for updates
• basically do anything I'd find on a forum

All to no avail and the issue still makes its appearance (happened while writing this post). Please help me, it's been over 2 hours....