I think the names of the two lists are clear and you have understood them according to what you wrote.

The recently opened files list contains the list of opened files in recent order. This list is the classic recent files list as versions of UltraEdit for Windows prior v22.00 have and most applications.

The recently closed files list contains the list of closed files in recent order. This list was introduced with UltraEdit for Windows v22.00.

It does not make really a difference on having never more than Number of recent files on File menu (customizable setting in configuration) files opened simultaneously in UltraEdit as in this case the last X opened or closed files can be found in both lists.

But some users have opened much more files than Number of recent files on File menu on which the recently closed files list becomes helpful. For example a user opens 50 files at once in UltraEdit. The recently opened files list with default 16 for Number of recent files on File menu contains the opened files 35 to 50. Now the user works with those 50 files and closes for example opened file 3, 20, 32 and 40. Some minutes later the user needs to open again file 20 and 40 for more modifications. But the recently opened files list contains only file 40. The simple solution is using in this case the recently closed files list which contains at top file 40, as second item file 32 and as third item file 20.

See also forum topic List of recent files is nested in submenu.

How the two recent files lists work is explained by me in my previous post.

I cannot reproduce with UltraEdit for Windows v2023.0.0.40 the behavior on having an opened and closed file just in recently opened files list on doing following:

1. Start UltraEdit and no file is opened or just a new, empty file.
2. Press Ctrl+O, browse to a file and open it.
3. Press Ctrl+F4 to close the just opened file.
4. Press Alt+F4 to exit UltraEdit.
5. Start UltraEdit again with no file or just a new, empty file opened automatically.

The opened and closed files lists contain both the file at top.

How each lists looks like after an exit of UltraEdit and next start depends on following criteria:

• How many files are opened automatically on startup?
• Which files are opened in which order during an editing session?
• Which files are closed in which order during an editing session?
• How many files are opened and closed during an editing session?
• What is configured for Number of recent files on File menu at Advanced - Settings or Configuration - Toolbars / menus - Miscellaneous?
• How files are handled by UltraEdit on exit according to the settings at Advanced - Settings or Configuration - File handling - Session options?

The recently closed files list can be very useful on starting UltraEdit, keep it running for hours, days or even weeks for viewing and editing dozens or even hundreds of different files like on large projects. There must be made a restart of Windows after four weeks to complete the installation of security updates of Windows. It is practically of no use on always opening, for example eight files at once and close these eight files also at once with having 16 configured for Number of recent files on File menu.

There is no configuration setting to see only the Recently opened files submenu in the traditional menu File or just the Recently opened submenu in contemporary menu File or on ribbon tab File.

In ribbon mode is displayed by default always the list Recently opened. The list Recently closed can be simply ignored on having no use for it.

The contemporary menu File contains just a few menu items and it could be therefore useful to have the recently opened files list directly at the bottom of the menu File which is possible with enabling the configuration setting Recent files list on file menu at Advanced - Settings or Configuration - Toolbars / menus - Miscellaneous.

The traditional menu File has lots of menu items. A listing of the recently opened files at bottom of the traditional menu File would be not very useful most likely for most users using the toolbar/menu mode with traditional menus depending on configured Number of recent files on File menu and main application window height respectively screen height. However, checking the configuration setting Recent files list on file menu at Advanced - Settings or Configuration - Toolbars / menus - Miscellaneous works also for traditional menu File.

The two different recent files lists are also very useful for people working with many opened files and using the command palette feature for quickly opening recently closed or recently opened files once again during an editing session. Opening files from the two lists using the command palette feature is much more efficient for advanced UltraEdit users who prefer doing as much as possible with their ten fingers on keyboard for efficient work with UltraEdit. Quick Open and opening files via the command palette as demonstrated in video UltraEdit's command palette and when I remember correct also in webinar UltraEdit Masterclass: An Introduction to the Swiss Army knife of text editors makes opening files much more efficient than using the recently opened / closed files menus with a pointing device.