Kival Mahadew

Have you enabled the customization option in thunderbird? You'll need to enable the `toolkit.legacyUserProfileCustomizations.stylesheets` setting in Config Editor. How to access the config editor: https://support.mozilla.org/en-US/kb/config-editor

Just a small note. The line `let mut excel: Xlsx = Xlsx::new(cursor).unwrap();` seems to run quite fast. The slowdown is happening here. ```rust excel.worksheets(); ``` It seems that https://github.com/tafia/calamine/issues/258 this...

Compiling with `--no-default-features` works as expected, but it seems this issue is not specific to the `csv-file` feature. `dtype-i8`,`dtype-u16` `dtype-categorical` also attempts to pull in these dependencies, where they did...