Yes. That is the point in that version. That you should be able to build your packet by exporting the extension and upload it via the web instead. They closed the marketplace link with GMS1.4 some time ago so you can't login anymore. So this would be the new way to update via the web instead.
I got this response from Yoyo when I asked them how to upload updates from 1.4:
Can you please go to File -> Preferences -> Marketplace and ensure that you have valid values by pressing the 'Check' button.
Can you please ensure that you have read and followed our
GameMaker Marketplace Help Articles
So check if the File -> Preferences -> Marketplace have a check button or something. 1.4.1804 dont have it. But maybe 1.4.9999 got it?