The WEBGL_compressed_texture_s3tc_srgb extension is part of the WebGL API and exposes four S3TC compressed texture formats for the sRGB colorspace.

MDN Reference

interface WEBGL_compressed_texture_s3tc_srgb {
    COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT: 35917;
    COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT: 35918;
    COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT: 35919;
    COMPRESSED_SRGB_S3TC_DXT1_EXT: 35916;
}
Index

Properties

COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT: 35917
COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT: 35918
COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT: 35919
COMPRESSED_SRGB_S3TC_DXT1_EXT: 35916