Allows you to later install .xpi plugins by simply uploading them
with the "PlugInstall" page. You need to first define an
administrator password (EWIKI_ADMIN_PW+ constant). There are also
remote .xpi plugin directories which you can browse and allow
for click-and-run addition of new extensions.

All plugins can be disabled through the admin interface, or at
least can be uninstalled again (for page plugins).

With a loaded phpjs interpreter you can also allow your users to
install the safe / sandbox-executed .jpi page plugins without
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You cannot modify the README.plugins file, but anyhow any ideas or suggestion should as usually get filed on BugReports, UserSuggestions or even better the README.plugins.Discussion.