The lujvo m1=l1 (text) is an equivalent/interchangable lujvo form of lujvo m2=l1 (text).
This refers to the fact that Lojban's lujvo can have many forms, all of which are considered to be equal in meaning automatically. See The Lojban Reference Grammar, chapter 4, section 5: https://lojban.github.io/cll/4/5/ Not to be confused with “synonymous” (selsmudu'i), which may apply to entirely different words. Cf. lujvo, mintu.