Please try cleaning the tmp directory of Piwik.

I deleted all files from the tmp directory. No change, the error still occurs.

Could you look up a more detailed error description with maybe a stack trace in the dev tools of your browser?

Affected code:

DataTable_RowActions_Transitions.registerReport({isAvailableOnReport:function(dataTableParams){return isPageUrlReport(dataTableParams);},isAvailableOnRow:function(dataTableParams,tr){return isPageUrlReport(dataTableParams)&&tr.find('> td:first span.label').parent().is('a')},trigger:function(tr,e,subTableLabel){var link=getLinkForTransitionAndOverlayPopover(tr);this.openPopover('url:'+link);}});DataTable_RowActions_Transitions.registerReport({isAvailableOnReport:function(dataTableParams){return isPageTitleReport(dataTableParams);},isAvailableOnRow:function(dataTableParams,tr){return isPageTitleReport(dataTableParams);},trigger:function(tr,e,subTableLabel){DataTable_RowAction.prototype.trigger.apply(this,[tr,e,subTableLabel]);}});DataTable_RowActions_Overlay.registerReport({isAvailableOnReport:function(dataTableParams){return isPageUrlReport(dataTableParams);},onClick:function(actionA,tr,e){return{link:getLinkForTransitionAndOverlayPopover(tr),segment:null}}});});

Can you check if the Transitions plugin is enabled in "Administration => Plugins"?

This is a bug as we're not checking everywhere whether this row action is actually available. We either need to load transitions.js in CoreHome or check for availability of this class

Same bug here

Can you check if the Transitions plugin is enabled in "Administration => Plugins"? This will solve it for now.

That solved it for me. Thanks.

It is.
I've disabled and re-enabled it - no effect.
And I've cleared the tmp-directory.

Did you clear the browser cache?

FYI: Issues fix for this here: #9713

Used Ctrl + F5 to reload (Firefox 44.0)

Thanks

Sorry, in my case, the Overlay-Plugin was disabled.
Re-enabling fixed the issue.
Maybe you want to extend fix #9713

Thx for letting us know @chris246 . There should be a fix for Overlay plugin in #9713

Cheers