If I receive an Excel spreadsheet (either .xls or .xlsx) or a Word document (.docx) as an attachment in Thunderbird it will only open in Read Only mode. I can save it & then open and it is fine but I cannot simply open the attachment directly without it being in Read only mode. I cannot uncheck the Properties "Read Only" check box because it is greyed out. [Later note added: Similar problem applies to jpegs where you can't rotate the opened attachment (ie this is a kind of non-editing mode too)] The yellow "Warning" bar that permitted editing is no longer appearing. Something seems to be preventing this yellow bar showing & that is why I cannot "give permission to edit". Is this a config issue ? This problem does not occur if opening from webmail or Windows Live Mail, only on Thunderbird. Same issue on Windows 7 (yes I know it is not supported) and Windows 10. I have Thunderbird 91.9.0 (release update channel) on both. I have several email accounts and the issue occurs with any email account and whether POP3 or IMAP. Also with Word/Excel attachments to emails stored in Local Folders which used to open fine. It is kind of like Thunderbird is trying to force me to save the file rather than open. This problem has only arisen following latest update (91.9.0). I have tried opening in Troubleshoot (Safe) Mode with add-ons disabled and the problem still exists. Can anyone tell me what to do about this please ? How can I make Thunderbird allow direct opening of an attachment in normal editing mode as it used to do ? How do I get the yellow warning bar back please ? What, if anything, do I change in config editor to make the yellow bar reappear ? Thanks for any help.