Hi, there's an interesting proposal here https://github.com/w3c/clipboard-apis/issues/9 for solving our "what about clipboard data from various native applications?" conundrum. The proposal is to let a page indicate what native clipboard identifiers it is interested in handling:
registerClipboardFormats({ "application/vnd.mathsoft.equation+xml":[ "XMCD Format", //Windows handle "MCD Format", //old Windows handle with the same format "XMCD_FORMAT", //Linux handle "com.mathsoft.xml"], // OSX handle "application/vnd.mathsoft.equation.meta+xml":[ "Provenance Data", //windows handle "PROVENANCE_DATA", //Linux handle "com.mathsoft.pd"] // OSX handle }); //returns: //{ // "application/vnd.mathsoft.equation+xml":true, // "application/vnd.mathsoft.equation.meta+xml":true //} And my current understanding of how this work work is https://github.com/w3c/clipboard-apis/issues/9#issuecomment-123829662 : What happens "under the hood" here is basically: The UA has a registry mapping the supported native clipboard types to the MIME types used for the clipboard API. For example, on Windows one of the entries is probably 'text/html' -> 'CF_HTML' When registerClipboardFormat() is called, for each MIME type (key) in the dictionary, it will check with the OS if the native clipboard knows about each format description on the list. The first matching format description the OS has registered (if any) will be added to the mapping table On reading from the clipboard, all data with the descriptions given in our mapping table will be exposed to JS with the corresponding MIME type. On writing to the clipboard, all data with a MIME type listed in the mapping table will be placed on the clipboard with the corresponding native description. Right? I'm not sure if implementors are happy about this. There's some pushback against allowing web contents to write binary data to the clipboard for security reasons - if you have vulnerabilities in local software (which is of course a when, not an if) an attacker can trick you into pasting some exploit payload into the vulnerable software. Also, I know that on Windows applications "register" their clipboard formats - how does this work on other platforms? Will the OSX clipboard be able to confirm that "com.mathsoft.xml" is a "known" type when the relevant software is installed? Comments welcome here or in the Github issue. -Hallvord R. editor of https://w3c.github.io/clipboard-apis/