I recently merged a somewhat stricter parsing for BBCode tags and it’s no longer allowed to use “values” without spaces. The value has to be surrounded by a pair of quotes if it has any spaces, otherwise they will be considered as different “parameters”.
Since the “pair of quotes” are somewhat different in various languages, I’ve only added what I thought was the most common ones.
Since the [details= plugin is somewhat popular with only one parameter, I will add a check for it so it can use values with spaces even though there are no quotes.