Sublime Text 2 is a text editor for OS X, Linux and Windows, currently in beta.

reveal_in_side_bar should scroll the side bar to show the file
reveal_in_side_bar should scroll the side bar to show the file. Currently I have to collapse the side bar in order to get it to do this. Also expand all and collapse all for the sidebar would be useful.

Make unsaved files bold in sidebar (folders section)

Add a code navigator, like panic coda

Convert encoding on the fly or at least when using "Save As..."
For the in-buffer-variant one could come up with a plugin tho...

Minimap colors should be configurable

Tag Highlighting / Angle Bracket Highlighting

Use KDE file dialogs
The one element that would improve the user experience on KDE the most is the usage of the native file open/save dialogs.
This is not only about the look, but also about functionality, e.g. favorite folders.
Implementation is straightforward by using the `kdialog` CLI utility.
One project that does this already is Chromium, using the xdg-utils.
Starting point reference: https://code.google.com/p/chromium/codesearch#chrome/src/third_party/xdg-utils/scripts/xdg-file-dialog

Text markers for Folding

Fixed position for open files block in sidebar

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