early 2019, there were reports of problems with the same type of keyboards in the 2018 MacBook Air. In May 2019, Apple modified the keyboard for the fourth time and promised that any MacBook keyboard with butterfly switches would be repaired or replaced free of charge for a period of four years after the date of sale. The Touch Bar MacBook Pro received mixed reviews. The display, build quality, and audio quality were praised but many complained about the butterfly keyboard; the little-used Touch Bar; and the absence of USB-A ports, HDMI port, and SD card slot. On May 4, 2020, Apple announced an updated 13-inch model with the Magic Keyboard. The four Thunderbolt port version comes with Ice Lake processors, updated graphics, up to 32 GB of memory and 4 TB of storage, and supports 6K output to run the Pro Display XDR. The two Thunderbolt port version has the same Coffee Lake processors, graphics, and maximum storage and memory as the 2019 two Thunderbolt port models. The 2020 13-inch models also gain 0.02 inches (0.6 mm) in thickness over the 2019 models. Apple silicon 13-inch with Touch Bar (2020–) On November 10, 2020, Apple introduced a new 13-inch MacBook Pro with two Thunderbolt ports with a brand new Apple M1 processor, directly replacing the previous generation of Intel-based 2020 baseline 13-inch MacBook Pro with two Thunderbolt ports. The M1 13-inch MacBook Pro was released alongside an updated MacBook Air and Mac Mini as the first generation of Macs with Apple's new line of custom ARM-based Apple silicon processors. This MacBook Pro model retains the same form factor/design and added support for Wi-Fi 6, USB4, and 6K output to run the Pro Display XDR, and increased the memory in the base configuration to 8 GB. The supported external displays was reduced to one, as the previous Intel-based models supported two 4K displays. The FaceTime camera remains 720p but Apple advertises an improved image signal processor for higher quality video. 14-inch and 16-inch (2021–) On October 18, 2021, Apple replaced the high-end 13-inch and 16-inch Intel-based MacBook Pros with 14-inch and 16-inch MacBook Pros, now equipped with the new Apple silicon chips, M1 Pro and M1 Max, Apple's second ARM-based chips and their first professional-focused chips. Apple addressed many criticisms of the Touch Bar MacBook Pro by restoring hard function keys in place of the Touch Bar, an HDMI port,