Google's John Mueller confirmed that the search company's 2014 guidance with faceted navigation remains true today - do not use non-standard URL encoding. That means do not use commas, brackets or ...
It's best to look at this issue from a technical point of view. I believe the W3C has rules out that URLs have to be "urlencoded" which means that special characters (and spaces are special characters ...
hanser Ars Legatus Legionis 24y 41,737 Subscriptor++ Nov 7, 2016 #2 You've discovered URL encoding: ...