Block applications on desktop during certain times
 

I would like to make certain desktop applications like Slack and Thunderbird unusable during certain times of the day (much like web browser plugins like Leechblock prevent you from checking certain websites during certain hours). Is there a way to configure this? I've searched online and have come up empty.

sounds like some sort of parental control system could help?

I guess maybe some cron job that changes the file based permissions could work. Some distro's have application control that could be adjusted by some cron job.