Don’t panic if you use Microsoft apps with Rosetta

Apple has announced Rosetta 2 technology for the M1, the chip designed by Apple for its Mac computers.

Apps written to use the Intel x86 architecture need to go through the Rosetta 2 translation layer in order to be used on Apple Silicon Macs, and that process can take time.

Microsoft has indicated that when its applications are opened on the Mac for the first time on models incorporating the M1 chip, the apps can be “bouncing” in the Dock for approximately 20 seconds while Rosetta 2 completes the translation of the instructions. The next times applications are opened, they will be available much faster. This is true for Word, Excel, PowerPoint, Outlook, OneNote, and OneDrive (Microsoft has since changed the drafting for a generic “will take longer” to open).

The delay in translation is likely to be influenced by how much or how little your code is optimized for Mac.

According to the Apple document on Rosetta

For the user, Rosetta is basically transparent. If an executable only contains instructions for Intel, macOS will automatically launch Rosetta and begin translating. When finished, the system opens the translated executable instead of the original. However, the translation process can take time, so users may find that translated apps open or move a little slower than they expect at times.