@IJustWantToReadDocs Thanks for raising this question! Firstly, apologies for the delay in responding here and any inconvenience this issue may have caused.
You can upload file to $web container the same way as you upload any file to azure storage. When using blob endpoint to upload content, there’s no difference uploading to $web container from any other user containers.
Hope this helps!
Kindly let us know if the above helps or you need further assistance on this issue.
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