I gave it a try this morning on my local machine with https://gerrit.wikimedia.org/r/c/operations/software/gerrit/+/756109 . In the web ui it shows:
> Plugin install error: Unrecognized plugin path /static/gerrit-theme.html from /static/gerrit-theme.html
The file that fails to load comes from Puppet: `modules/gerrit/files/homedir/review_site/static/gerrit-theme.html` which I guess is an HTML plugin for which support is removed in 3.4 https://www.gerritcodereview.com/3.4.html#html-plugin-support-is-removed. @Paladox you told me about it, have you ever made a patch to migrate or do you have any guidance as to what needs to be done? :]
> HTML plugins should be migrated to JavaScript plugins. This also implies Polymer 2 plugins wouldn’t work any more. See also [[ https://groups.google.com/g/repo-discuss/c/YJY8oQZZo44/m/wt-OAosQBAAJ | this announcement for more details ]].
From the javascript console:
```
initResin
TypeError: URL constructor: /static/gerrit-theme.html is not a valid URL.
Na http://127.0.0.1:8080/elements/gr-app.js:1
_getPluginKeyFromUrl http://127.0.0.1:8080/elements/gr-app.js:317
_updatePluginState http://127.0.0.1:8080/elements/gr-app.js:317
_failToLoad http://127.0.0.1:8080/elements/gr-app.js:317
loadPlugins http://127.0.0.1:8080/elements/gr-app.js:317
loadPlugins http://127.0.0.1:8080/elements/gr-app.js:317
...
Plugin loaded separately: /static/gerrit-theme.html
Runtime info
Gerrit UI (PolyGerrit)
Gerrit Server Version: f712a44
Plugin codemirror-editor installed. gr-app.js:317:14209
Plugin delete-project installed. gr-app.js:317:14209
Plugin lfs installed. gr-app.js:317:14209
Plugin reviewers installed. gr-app.js:317:14209
Plugin zuul installed.
```