L key randomly stops working in InDesign

I have this same issue, and it's a terrible bug that should be fixed. Why would typing just the 'l' character ever be a keyboard shortcut in the midst of inputting text? 

Hi there,

Sorry about this trouble. It generally happens when there is a conflict of keyboard shortcuts with other applications/extensions/plugins. Try booting the system into Safe Mode (https://support.microsoft.com/en-in/help/12376/windows-10-start-your-pc-in-safe-mode) and check how it works there. It starts your system to perform certain checks and prevents third-party software/ services from automatically loading or opening. If it works fine in Safe mode, then there is some third-party service or application like antivirus, plugins, or web extensions conflicting with the InDesign.

Feel free to let us know if you still need assistance. We'd be happy to help.

Thanks & Regards,
Anshul Saini

Nothing has helped. I completely uninstalled InDesign including all my customized settings and preferences, reinstalled fresh copy, and this same issue is still occuring. I'll be typing along just fine, having used all the letters normally, and the L will stop working, and all other text then turns "thin" and compressed. I have to completely reboot my laptop to reset it. 

I can think of no rational reason this would be happening, especially if the key is fine in other programs. I can only assume it is related to a particular shortcut you have assigned? You could check that by heading to Preferences > Keyboard shortcuts and hitting L at the bottom, and seeing what pops up?

That is VERY random. Maybe a trash/reset of the InDesign preferences would help you narrow down the source of the problem?

https://community.adobe.com/t5/indesign/reset-indesign-preferences-and-other-troubleshooting/m-p/11990234