Firmware Version 1.1.1 incorporates the following fix and enhancement:
1. When the RF100-500mm* F4.5-7.1 L IS USM lens is attached, an image stabilization effect of approximately six stops is achieved through collaborative control with the in-lens image stabilization.
*Focal length 500mm, Based on CIPA(Camera & Imaging Products Association) standards.
2. Fixes a phenomenon in which the IS capabilities may be degraded when performing continuous shooting in cases where the RF100-500mm F4.5-7.1 L IS USM lens is attached to the EOS R5 running firmware version 1.1.0.
Firmware Version 1.1.1 is for cameras with firmware up to Version 1.1.0 If the camera's firmware is already Version 1.1.1, it is not necessary to update the firmware.
Q&A Section:
Preparations for the firmware update:
In the folder you downloaded are the firmware (EOSR5111.FIR / file size: 46,130,112 bytes) and instructions on the firmware update procedures (a PDF file in five languages: Japanese, English, French, Spanish, and Simplified Chinese). Before starting the firmware update operations, please be sure to check the procedure in accordance with the instruction.
Firmware link:
https://www.canon.com.au/cameras/eos-r5/support?option=drivers