[feature]: Missing MIME type support for Microsoft Office macro-enabled and binary files
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@vihar is already working on this.
Since May 10, 2026.
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Description
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Summary
Some valid Microsoft Office file formats are currently missing from the allowed MIME type list.
The main affected files are Excel .xlsb and .xlsm files, but the same issue may also affect other Office formats such as macro-enabled documents, templates, add-ins, and slideshow files.
Examples of missing MIME types include:
application/vnd.ms-excel.sheet.binary.macroEnabled.12
application/vnd.ms-excel.sheet.macroEnabled.12
application/vnd.ms-excel.template.macroEnabled.12
application/vnd.ms-excel.addin.macroEnabled.12
application/vnd.openxmlformats-officedocument.spreadsheetml.template
application/vnd.ms-word.document.macroEnabled.12
application/vnd.ms-word.template.macroEnabled.12
application/vnd.openxmlformats-officedocument.wordprocessingml.template
application/vnd.ms-powerpoint.presentation.macroEnabled.12
application/vnd.ms-powerpoint.template.macroEnabled.12
application/vnd.ms-powerpoint.slideshow.macroEnabled.12
application/vnd.ms-powerpoint.addin.macroEnabled.12
application/vnd.openxmlformats-officedocument.presentationml.template
application/vnd.openxmlformats-officedocument.presentationml.slideshow
### Why should this be worked on?
Microsoft Office files are commonly used in business environments, especially Excel spreadsheets.
Files such as `.xlsb` and `.xlsm` are valid Excel formats and are frequently used for reports, financial spreadsheets, operational controls, data exports, and macro-enabled workflows.
Without support for these MIME types, users may be unable to upload or attach valid documents even though the file format is widely supported by Microsoft Office.
Adding these MIME types improves file compatibility, reduces false rejections, and makes document handling more consistent with real-world business usage.
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