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Add the download button and the open button to download or open profile picture and media in the posts, stories, and highlights in Instagram
< Feedback on Instagram Download Button
I use Firefox (Windows10) and have download buttons on both stories and posts, albeit not on saved post, but I don't think that was supposed to be addressed in this update.
From what I have observed: On some 'saved' posts, you will get the option to download them. The difference seems to be if the profile is public or private. It looks like instagram recently changed behavior and is removing the 'share' arrow button on accounts that are private. Unfortunately, the script is using the existence of this button to add-on the download buttons and since it may not exist, it breaks the script.
From 1.17.6, the has
selector has been removed. Please update and try again, if you are using Firefox.
About the layout, I will investigate this issue.
no download button on firefox even with the last update