Add .dropboxignore directory to exclude folders without using selective sync

I've ran several tests on mac and PC:

•  Selecting 'don't sync' via right click menu - confirmed. folder will remain on the machine executing the command and will dissapear from all others including the web app.
• Selecting the opposite via right click (sync to dropbox) menu - confirmed. The folder will reappear on the other computers and the web app. 

So the feature definitely isn't per machine in terms of sharing but can be run by anyone (which could be kind of dangerous i suppose).

Given its a very basic line of code in pwsh (PC) and terminal (Mac/Linux) there are a myriad of ways to trigger it as the OP mentioned would like. I have got the following to work:

• Executing commands via context menu (depending on your system, you may not have the command 'dont sync to dropbox' inside the dropbox context menu).
• Executing via system scheduler periodically and;
  • triggered upon launch of an app;
  • triggered by launch of an app AND presence of Folder.ignore file;
  • triggered by running shortcut of Folder.ignore
  • Setting Folder.ignore as environment variable DROPBOX_IGNORE_PATHS which could be shared with a team and provides a master list of all the folders currently in this state. could live on a server etc.
  • there are so many ways to trigger it on the Mac i won't waste anyones time writing it all down. 

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