CodeLite IDE

I mean these tabs on the attachment.

Here is the tab default sort behavior:

By default all files are placed from left -> right in order they opened.

Unless you opened an editor using F2 (shortcut for "swap header/implementation file") - in this case, the file is placed to the right of its sibling (file.cpp + file.h are considered "siblings")

You can always drag/drop files or move them around using the designated keyboard shortcut