Attempting to install the plugins, and they do not.
You click install, the screen for loading cycles, and then takes you back to the currently installed plugins page.
I have check the permissions on the plugins directory, and I believe they are correct. (Not %100 sure what they should be, but they match the rest of the system, and I even tried for trouble shooting steps to give them 777, then reverted back to what they had because I saw no difference)
I did install a language pack to confirm that would work, and it does!
Not sure what logs I would look at for this.
osTicket Version: v1.10.4-111-g19712cd8 (19712cd) — Up to date
Web Server Software: Apache
MySQL Version: 5.7.23
PHP Version: 7.0.32