Is there a way to temporarily disable renderers/pre-processors?

[mightyiam]

Context: Michael-F-Bryan/mdbook-linkcheck#68

Such as the flag proposed there: --disable=linkcheck,index

[ISSOtm]

Would there be use cases for temporarily enabling some as well? (Also, this would require two flags, one for preprocs and one for renderers, unless the arg syntax is made to allow disambiguation when necessary, e.g. --disable p:pandocs,r:pandocs.)