How entering quadruplets (or just their brackets)?

I would like to force some quadruplet brackets for plain 16th notes, which are however irregularly grouped (see attached example). I tried inserting a tuplet for a 4:4 fraction, but that seemingly is not supported. Is there perhaps another way? Alternatively, is there a way perhaps to insert some mere brackets attached over the notes?

Thank you!

With either the first note selected or the caret invoked there’s no reason why ; 4:4 Enter shouldn’t work (and indeed it does seem to work fine here). If the first note selected is a quaver/eighth you’d need to specify 4:4x in order to tell Dorico you wanted a 16th note tuplet, and there’s some manual beaming to do.

Quickest way is probably to do a single 4:4x tuplet at the start, F to flip above, then hit Q to turn on chord mode(!), then R however many times to repeat it.

Thanks a lot for your quick and very helpful response. That worked great!

No idea why I struggled before. I now simply turned existing notes into those quadruplets. First I thought I instead have to write these bars with these tuplets again, and there I had issues. Anyway, not anymore. Thanks again!