This ticket should be rejected. A regular expression created with the global flag is stateful (i.e., the lastIndex property is checked and used by the exec and test methods.) On sufficiently old browsers (pre js 1.5), this makes the RegExp object itself stateful, i.e., not instances, but the RegExp constructor is mutated!
Using a regex with the global flag set will already ruin the results of re-seq, re-find, etc. I could see re-seq using a clone of the input regex with the global flag set as an optimization to avoid string slicing, but we certainly shouldn't provide a public interface to create them.
See also CLJS-776