If you have no permissions or access to command line directly, you can do e.g. one of the following:

1. Create a job with shell/batch step that will trigger restart from Jenkins installation folder
2. Install/update some plugin while checking "restart after installation" (at least this works in old versions)

Both above are hacks, but I actively used them in a very restricted environment where no one wanted me to restart Jenkins, huh.

If you have no permissions or access to the command line directly, you can do e.g. one of the following:

1. Create a job with shell/batch step that will trigger a restart from the Jenkins installation folder
2. Install/update some plugin while checking "restart after installation" (at least this works in old versions)

Both above are hacks, but I actively used them in a very restricted environment where no one wanted me to restart Jenkins, huh.