Eclipse fails to start after some manipulations of plugins

[wiresketch]

I suspect that I discovered a p2 issue that affects the Flatpak distribution of Eclipse. Doing some steps can break the installation and it cannot be repaired even using "-clean" argument, at least this is what happens in my case. I suspect this is a p2 problem so I've filed the issue there. Please see the referred issue for more details:
eclipse-equinox/p2#555

Perhaps others can try the outlined steps and confirm that the issue is reproducible.

[Mailaender]

It is reproducible and I don't have a workaround for it which makes it quite serious as there is no way to install the Plug-in Developer tools for example. Changing the timestamp of eclipse.ini does not fix it. Only deleting .eclipse and starting without plugins works.