> there are a few rare occurrences where we can apply the so-called *muta cum liquida* rule
> In Sanskrit such an indulgence is rather rare and appears to be more
> frequently applied in Prakrit poetry and "Epic" Sanskrit. In the latter
> case several types of consonant clusters do not cause the preceding
> syllable to be guru.

By the way, Colebrooke already described the phenomenon in 1808:

"By poetical license, a vowel may be short before certain conjuncts (viz., pra and hra; as also bra and kra. [...]."
(H. T. Colebrooke, "On Sanskrit and Prákrit Poetry", in: Miscellaneous Essays, Vol. 3, London 1873, p. 65)

In his PhD thesis of 1988 Michael Balk noted the same metric license for the Udānavarga (especially for the case of pr- and br-). See M. Balk: Untersuchungen zum Udānavarga. Unter Berücksichtigung mittelindischer Parallelen und eines tibetischen Kommentars. Marburg 2011 (Indicat et Toberica. 53), pp. 39-42.

With best regards,
Roland Steiner