Main ui > all black

I am on the Eclipse IDE environment and after an update of openhab-distro to latest snapshot when I start OH3 I can access the Main UI but it’s all black like in the picture:
oh

Is there anything I can do to reset the Main UI ?

In general, how can I clear the cache using Apache Felix OSGi launcher?

looking to the browser dev console I read this error:

Uncaught (in promise) TypeError: Cannot read properties of undefined (reading 'locale')
    at u.loadRootResource (app.js:38)
    at Array.<anonymous> (app.js:17)
    at u.dispatch (app.js:23)
    at u.dispatch (app.js:17)
    at app.js:33

@ghys any idea?

I have found it’s related to this issue in openhab-distro.
However, I think web ui should give some meaningful message in case the OH3 core is not completely started (i.e. some bundle required by main ui did not start).

opened a new issue for main ui