Jenkins UI broken post restore

Jenkins setup:
Jenkins: 2.426.3
OS: Linux 4.14.334-252.552.amzn2.x86_64 x86_64
Java: Java 11

Unable to post plugin list and will now explain why. Restored Jenkins from backup, the service is up and I can curl the Jenkins port and it returns a 200

However the Jenkins UI seems to broken, when I go to the URL, the browser shows some links which when clicked state that the page can’t be found and some very large icons, so large they fill the browser window.

I’m guessing its something plugin related but having looked in the jenkins.log I can’t see anything specific that could be causing this.

Has anyone seen this before please?