Greasy Fork is available in English.
在Instagram页面加入下载按钮与开启按钮，透过这些按钮可以下载或开启大头贴与贴文、限时动态、Highlight中的照片或影片
This script still works on my computer, maybe the changes are only for your location or don't propagate to my location yet.
Can you provide your evn. info (eg. language, brower version, O.S. version...)?
The script is on its latest update. No download button appears for regular posts. Seems to still function on Stories, however.
Then there may be a chance of conflicting scripts on users' end.
The main feed doesn't show the download button. Stories work, home page doesn't.
Please update to 1.17.4 and try again.
No longer working as of late. Instagram must have changed something in their code.