Dan. initial [sr] became [str]; [sr-] > [str-]

Dan. initial [sr] became [str]; [sr-] > [str-]
According to the Comparative Tables initial [sr] became [str] (PE19/21), but there are no attested examples of this change in The Etymologies.

Phonetic Rule Elements

[sr-] > [str-] ✧ PE19/21 (sr- > str-); PE19/21 (sr- > str-)