Closed as fixed:
Notes:
I brought µMatrix more in line with µBlock for web pages which are incrementally updated. This happens a lot here on Github: often, clicking on a link will not cause a new page to reload, but rather the content of the current page will be just updated. The URL in the address bar changes though.
An extreme case of this behavior is Google Maps, where whenever you pan/zoom, the URL in the address bar will change, yet the page's content is just updated, it is not a new document reloaded. Before fix to issue #37, a whole new matrix was created each time the URL in the address bar changed. This doesn't make much sense for Google Map, or even Github, and whatever site make use of incremental update of web pages.
So the new behavior is to re-use whatever matrix was in use for web pages which incrementally update. This way of working makes more sense when one has to modify rules through the matrix: this way a user will be able to finalize his rules by saving them. The former behavior could have impeded this.
Note that with the new behavior, it is now rather easy to end up with one or more thousands of distinct net requests for site such as Google Maps.
Hopefully the new behavior will not trigger new issues.