The URL you're trying to access requires that requests be sent using POST (like a form submission). The button below allows you to retry accessing this URL using POST. URL being accessed:</p><p><tt>http://localhost:8081/pluginManager/plugin/ant/makeDisabled</tt
Method Not Allowed. Weird.
right now at 2.107.1
I hope this is just a typo 2.121.1.
Interestingly, this is all from https://github.com/jenkinsci/jenkins/blob/master/core/src/main/resources/hudson/PluginManager/installed.jelly and that specifically sends an AJAX POST request when toggling a button. Unclear how that could end up being GET. I also cannot reproduce this problem at all with lts-alpine at 2.121.2. In the wizwrd, I customized installed plugins, accepted the admin user, and set the root URL. Immediately afterwards I successfully disabled a plugin.