The GL_VERSION and GL_SHADING_LANGUAGE_VERSION strings begin with a version number.
But the OpenGL ES 3.0/3.1/3.2 specifications says:
The VERSION string is laid out as follows:
"OpenGL ES N.M vendor-specific information"
The SHADING_LANGUAGE_VERSION string is laid out as follows:
"OpenGL ES GLSL ES N.M vendor-specific information"
I think the latter is correct, because it is compatible with OpenGL ES 2.0 behavior.
https://github.com/KhronosGroup/OpenGL-Refpages/blob/f50027c1c911e019648a6a08176aa6813de66d47/es3.0/glGetString.xml#L135-L149
https://github.com/KhronosGroup/OpenGL-Refpages/blob/f50027c1c911e019648a6a08176aa6813de66d47/es3.1/glGetString.xml#L135-L149
https://github.com/KhronosGroup/OpenGL-Refpages/blob/f50027c1c911e019648a6a08176aa6813de66d47/es3/glGetString.xml#L135-L149
But the OpenGL ES 3.0/3.1/3.2 specifications says:
I think the latter is correct, because it is compatible with OpenGL ES 2.0 behavior.