this is is just a guess, but chrome has started to drop support for the old MutationEvent api https://developer.mozilla.org/en-US/docs/Web/API/MutationEvent firefox still support it but ti was deprecated in 2012 with the intorductoin of Mutation Observers and chrome disabeld supprot by default in 2024 i belive it now actully removed but i could be wrong. heat-dashboard hasd not been maintianed for quite a while https://github.com/openstack/heat-dashboard/commits/master/ my guess is heat (which is usign angular in some of it sviews) may still be using the mutation events api instead of mutation observers, either indreictly via jquery `bind()` instead of `on()` or via angular. it would be good to check you javascript console in the browswer and see if there are any errors. i belive if you try to registry an event listener via the old api chrome prints a warning or error in the console horizion has at leat one useage of muationObservers https://github.com/openstack/horizon/blob/2511454a318b90dd3f59bea6c45c2d35ee... but in the same file its using the old api that does nto work anymore https://github.com/openstack/horizon/blob/2511454a318b90dd3f59bea6c45c2d35ee... i suspect that its something like that given it works in firefox but not chrome. On 22/04/2025 15:50, Jorge Merlino wrote:

Hi folks,

There is an issue with Horizon's heat template generator when using chrome or a chrome based browser.

It can be easily reproduced by going to the Project / Orchestration / Template Generator menu. There are icons on the top of the screen that can be dragged into the canvas below. That works fine in Firefox but does not work in Chrome. When the icon is dragged over the canvas in Chrome it shows a little green plus sign next to it which does not appear in Firefox and dropping the icon does nothing. I could not see any errors show in the browser console or the debugger.

Tested on horizon 22.1.1 (openstack Yoga)

Thanks for your help Jorge