Besides the existing "Extension" column I would suggest to add two columns called "Extension (uppercase)" and "Extension (lowercase)". For example when you have a big list of files of the same type (e.g. "txt"), then the extension column makes it easy to recognise that they're all of the same type. But if some are listed as "TXT" and some are listed as "txt", then it's harder to recognise this at first glance (because the human eye can handle periodic patterns/textures very well).
I also wanted to say that Directory Opus is just incredible. I've tried dozens of file manager, but Directory Opus is simply outstanding. It was the only file manager that I could configure to suit my needs perfectly (It took some time, but that was totally worth it). A big thanks to all the developers and keep up your great work! Afaik there is nothing comparable out there.
What about a slightly different thing where, instead of an extra couple of columns, there was a setting in Preferences like:
Change case of extensions:[ul][li]Uppercase[/li]
[li]Lowercase[/li]
[li]Leave as-is[/li][/ul]
and this then affected both the Extension column and the filename column?
A bit like the option which lower-cases all upper-case filenames, but it only looks at and only affects extensions.
I know I dislike the way Photoshop keeps using JPG and so on instead of jpg. I might use this myself.
Sounds also good. Though I would prefer if I could keep "real" filenames (e.g. "file.TXT") and just have lowercase extensions in the extension column (e.g. "txt" for "file.TXT"). A "real" filename column is important when I rename files and when I'm using them together with my Linux system (which is case sensitive). But the lowercase extension column would give a good overview.
Hmm ... well, it really depends on how much work the implementation of the feature would be. Theoretically one could add separate options for the filename column and the extension column (similar to the proposal in your post). Or alternatively add extra columns for both (similar to my first post). But I don't want this to mean too much work. So in the end, the developers should decide what's the easiest and best implementation, if they decided to add this feature.
