Opening mhtml files with Firefox

At times I get saved webpages by people using the mhtml format (Google Chrome uses that format) to look into.
While it is a plaintext format with added binaries, it would be much work for just one single such file to extract the html data. I did so in the past, but it would be easier to just have a Chrome installed as well, but I don`t like having Chrome, I would be more happy when FFx is the only browser I need.

I tried looking for an mhtml supporting AddOn on but that resulted in 215 results, and the whole first page of results seems to not have one AddOn that would support mhtml.

I hope it is okay to ask for a certain kind of AddOn on here, but I did not see a more appropriate sub-forum to ask in.


I have not heard of any extensions to read MHTML files in Firefox 57+.

Considering the number of interested users, I can only assume that it’s difficult to implement using the WebExtensions APIs.

Same problem. Need to use MHTML-files, as the most useful and compact cross-platform media-format. For saving the data in Firefox I use the SingleFile add-on. But then, this saved file can not be opened in Firefox, but it can in all other browsers. Why? How? 8-/

That is strange. The idea behind SingleFile is to create universal HTML files. Or are you using SingleFile to save in MHTML format?