On linux Chrome flash have hardware acceleration disabled. This makes Glitch a little laggy sometimes. In that case create a folder /etc/adobe and inside make a file named mms.cfg containing:
EnableLinuxHWVideoDecode=1
OverrideGPUValidation=true
Keep in mind that this can break some flash stuff, because flash hardware acceleration in linux is in early stage. They make it use VDPAU but there are still bugs, so be warned.
EDIT: VDPAU utilizes NVIDIA cards and you need their proprietary drivers. It also is supported by 9000 series and later chips.
Maybe there other drivers that use VDPAU dunno actually.