New sandbox approach results in blank page on https://musik.yousee.dk

[dstillman]

https://forums.zotero.org/discussion/119701/bug-zotero-connector-blocks-website

[adomasven]

Seems like we'll have to go to offscreen page translation afterall. There's no safe way to inject elements into pages without breaking them. Shame the offscreen API wasn't available when originally implementing the MV3 plugin, but it won't be too much work to move it offscreen, since the main task there was extracting and modularizing translate.