Steps to (maybe) fix hardware graphics acceleration

Command to verify hardware acceleration (only works inside xorg session):

Positive example:

$ glxinfo | grep render

direct rendering: Yes
    GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer, 
    GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer, 
Extended renderer info (GLX_MESA_query_renderer):
OpenGL renderer string: Mesa DRI Intel(R) HD Graphics 530 (Skylake GT2) 
    GL_ARB_conditional_render_inverted, GL_ARB_conservative_depth, 
    GL_NV_conditional_render, GL_NV_depth_clamp, GL_NV_packed_depth_stencil, 
    GL_ARB_conditional_render_inverted, GL_ARB_conservative_depth, 
    GL_MESA_window_pos, GL_NV_blend_square, GL_NV_conditional_render, 
    GL_OES_element_index_uint, GL_OES_fbo_render_mipmap,

Negative example (llvmpipe (LLVM 6.0, 256 bits) means it’s using software rendering):

$ glxinfo | grep render

direct rendering: Yes
    GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer,
    GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer,
Extended renderer info (GLX_MESA_query_renderer):
OpenGL renderer string: llvmpipe (LLVM 6.0, 256 bits)
    GL_ARB_conditional_render_inverted, GL_ARB_conservative_depth,
    GL_NV_conditional_render, GL_NV_depth_clamp, GL_NV_packed_depth_stencil,
    GL_ARB_conditional_render_inverted, GL_ARB_conservative_depth,
    GL_NV_blend_square, GL_NV_conditional_render, GL_NV_depth_clamp,
    GL_OES_element_index_uint, GL_OES_fbo_render_mipmap,

Session type:

$ loginctl show-session c2 -p Type
Type=x11

Make sure these are installed:

linux-modules
linux-modules-extra
libegl1-mesa
libgl1-mesa-dri
libgl1-mesa-dri
libgl1-mesa-glx
libglapi-mesa
libgles2-mesa
libglu1-mesa
libwayland-egl1-mesa
mesa-utils
mesa-vdpau-drivers

Kernel versions working:

4.10.0-33-generic
4.15.0-15-generic

Linux specific packages:

dpkg -l | awk '{ print $2 }' | grep ^linux
linux-base
linux-firmware
linux-headers-4.15.0-15
linux-headers-4.15.0-15-generic
linux-modules-4.15.0-15
linux-modules-extra-4.15.0-15
linux-image-4.15.0-15-generic
linux-image-extra-4.15.0-15-generic
linux-libc-dev:amd64
linux-sound-base

apt install linux-headers-generic linux-generic