Maintainers for libgl1-mesa-glx are Debian X Strike Force <debian-x@lists.debian.org>.
You may want to refer to the following packages that are part of the same source: libd3dadapter9-mesa, libd3dadapter9-mesa-dev, libegl-mesa0, libegl1-mesa, libegl1-mesa-dev, libgbm-dev, libgbm1, libgl1-mesa-dev, libgl1-mesa-dri, libglapi-mesa, libgles2-mesa, libgles2-mesa-dev, libglx-mesa0, libosmesa6, libosmesa6-dev, libwayland-egl1-mesa, libxatracker-dev, libxatracker2, mesa-common-dev, mesa-drm-shim, mesa-opencl-icd, mesa-va-drivers, mesa-vdpau-drivers, mesa-vulkan-drivers.
You might like to refer to the libgl1-mesa-glx package page, to the Package Tracking System, or to the source package src:mesa's bug page.
If you find a bug not listed here, please report it.