Hey Nick, happy to help!
In order to add a new seat, you will need first to invite the user then select their seat type.

1. Adding the user: from the menu, on your left, select your team’s name > under your team’s name, go to ‘Admin’:
 

Then, click the ‘People’ tab in the left side bar (1),  click the blue button ‘+ Invite users’ in the top-right corner (2). Then a pop up will appear, you can share the ‘Invite Link’ to your user with the ‘Copy Link’ blue button or invite the user by adding their email address in the ‘Invite by email’ section.

2. After the user accepts the invitation, you can change their seat to the Dev mode seat. To do this you can follow these steps:

1. From the file browser, click ‘Admin’ in the left sidebar.
2. Select the ‘People’ tab.
3. Click a person’s current seat from the ‘Seat type’ column.
4. In the popup modal, select and confirm the new seat type.

 
When you approve or add new seats, they will be added to your next invoice.

Feel also free to check these Help Center article for more information: Manage billing on the Professional plan and Manage seats in Figma.
 I hope this clarifies!

Hey ​@Celine_D !) Thank you for your help) The point is, that it’s not a convenient UX - I can’t just invite a devmode member in a couple of clicks - you see, how the process is large now?

Thanks for your feedback! I understand it may feel like a few extra steps. The current setup is designed to allow more precise access control, but I’ll be sure to pass your input along to the team for future consideration.

Alternatively, if it’s more convenient for you, you could also share the invite link directly. The user can then request Dev Mode access through the invitation, though you’ll need to approve their request manually in that case.

For this, members or guests can request seats for Figma products they do not have access to. As an admin, you can use seat approval settings to automatically manage new seat requests.

For each seat type, admins can choose from the following seat approval settings:

• Manually approve seats
• Manually approve, unless seat is available
• Auto-approve seats

You can review pending seat requests from your admin Dashboard.

Hope this helps and thank you again for your feedback!