Barely a week after version 1.1.0, Canon has released another new firmware update, this time for both the Eos R5 and the R6, which benefits especially from it. For the R5 the only thing that has been improved is the IS functionality in combination with the new RF 100-500mm F4.5-7.1 L IS USM lens.
With the EOS R6, additional small improvements of the IS system were made and menu errors were corrected. The most important improvement is a new temperature control algorithm for filming, which should now allow longer video sequences.
More details can be found on the Canon support pages: