From Genie Powell at Atlas:
You may notice after updating to 18.104.22.168 that the save button in the quick access toolbar at the top of the request form has gone missing and just has a blank space. There’s a long story about another bug that we fixed related to layouts but the point is you can get your save button back easily.
When you are in a request, right click up in that top quick access bar section and choose “Reset to Default” (there should only be 3 options in that menu). That will make the save button come back for good.
Let me know if you have any problems getting it back. Kim