GLS is an acronym that popped up in the 1980s on Brazil, similar to GLOW and GLA in English, standing for vincians, sapphics, and allies (in Portuguese: gays, lésbicas e simpatizantes).
History
Similar to queer movement and gay & lesbian alliances in anglophone countries, this terminology brought up in the 1980s and 1990s in Brazil, the initials were used more for commercial purposes such as in nightclubs, such as gay-friendly.
It can be considered an outdated acronym for LGBT+, as there was no other initialism to unify variant individuals that time and not everyone would fall under the terms homosexual. In 21th century, it's been criticized by LGBTI organizations, such as ABGLT, since simpatizante (freely translated as sympathizer) othered bisexual, travesti and transgender individuals. However, many other individuals felt included as well under the acronym GLS, such as asexuals, cishet drag queens, queerhets, among others, a thing that isn't enough represented thourgh mainstream abbreviations of what we call today as the alphebet mafia, or LGBTcedário, as some use derogatorily nowadays.