[BUG] Bring back support for long file names and timestamps in M20 L T g-code command

[arekm]

Please, before you create a new bug report, please make sure you searched in open and closed issues and couldn't find anything that matches.

Printer type - MK4, MK3.5

Printer firmware version - 4.5.4, 5.2.0

Original or Custom firmware - Original

Describe the bug

M20 command issued over serial doesn't list long file names and doesn't list timestamps.
This feature existed for many years in MK3 firmware but is missing from MK4 firmware.

How to reproduce

Issue

M20 L T

over serial.

Send: M20 L T
Recv: Begin file list
Recv: T-NUT_~1.GCO
Recv: End file list

Expected behavior

Long file names and timestamps (in form of hex numbers) are shown.

Send: M20 L T
Recv: Begin file list
Recv: T-NUT_~1.GCO 1061513 0x5690a164 "T-nut_M3_x12_20m.gcode"
Recv: End file list

More info
Code for that exists in MK3 firmware and also Marlin 2.1.2+ (
guarded by LONG_FILENAME_HOST_SUPPORT
https://github.com/MarlinFirmware/Marlin/blob/2.1.2.2/Marlin/src/sd/cardreader.cpp#L304-L314
https://github.com/MarlinFirmware/Marlin/blob/2.1.2.2/Marlin/src/gcode/sd/M20.cpp#L46

and M20_TIMESTAMP_SUPPORT defs,
https://github.com/MarlinFirmware/Marlin/blob/2.1.2.2/Marlin/src/sd/cardreader.cpp#L327C3-L336C8
https://github.com/MarlinFirmware/Marlin/blob/2.1.2.2/Marlin/src/gcode/sd/M20.cpp#L47

so will be easier to see what's needed for backporting).

[Prusa-Support]

Thanks for reporting.

Our developers will look into this.

Michele Moramarco
Prusa Research

[bkerler]

I just wrote a PR #3765 for this issue.

[github-actions]

This issue has been flagged as stale because it has been open for 60 days with no activity. The issue will be closed in 7 days unless someone removes the "stale" label or adds a comment.

[github-actions]

This issue has been closed due to lack of recent activity. Please consider opening a new one if needed.

[danopernis]

This shouldn't have been closed since there are several PRs basically solving it.

[timur-tabi]

This is yet another feature that is missing in the MK4 firmware that was present in MK3.

[timur-tabi]

Thanks for reporting.

Our developers will look into this.

It's been almost a year and a half. Maybe they should look harder?