Sorry for the late reply. I just now saw your second post. There isn't a "standard" for returning to the top of the page. As you know the icon is interactive, i.e. a link associated with it, if it has text it is fine. However if the option to "hide" the text is used the interactive icon appears blank thus an individual using a screen reader can not identify it's purpose.
With that in mind I would suggest that the text that would be displayed if it was not hidden be used for the aria-label. My reasoning being that your plugin could also be used on sites that are non-english and/or multilingual. I also remember that you provided the ability to set an "override" for the text via the language overrides section of Joomla. I have used that feature to set the text for it on many multilingual sites. So whatever is entered would be what is used for aria-label regardless of whether or not the text is hidden. This would also allow non-english sites to customize the text via the language section for any site languages being used and have it apply to the aria-label as well.
I hope this helps!
Thanks for working on this! I really appreciate you being open to adding this feature request!
