Thanks john r red-horse and Villy Kruse! I remember to not run fsck with mounted volumes and prefer to ask before to do anything 
Realy, after unmount volumes, this is the score:
sudo umount /boot/efi
sudo umount /boot
sudo fsck /dev/sdb1
fsck from util-linux 2.40.4
fsck.fat 4.2 (2021-01-31)
/dev/sdb1: 24 files, 4935/153290 clusters
sudo fsck /dev/sdb2
fsck from util-linux 2.40.4
e2fsck 1.47.2 (1-Jan-2025)
/dev/sdb2: clean, 31/65536 files, 81781/262144 blocks
False alarm so 
Guys, confirmed, Fedora version 39 does not display the “error” message. Fedora versions 41 and 42 are the ones that display the “error” message. What could have changed from version 39 to versions 41 and 42? Including when booting from the Live CD…
Maybe I’ll give up, it’s annoying for everyone, you know? 
Releases/40/ChangeSet - Fedora Project Wiki
Releases/41/ChangeSet - Fedora Project Wiki
Releases/42/ChangeSet - Fedora Project Wiki
Did you check the changelog? Links above.
Thank You ilikelinux! (I like it too ). I searched and found nothing in changelogs. But I ask AI and answers follow below.
Ask part first mode (portuguese (translated)):
What changed in efi boot in Fedora Linux versions after version 39 that can cause the error "Failed to open \EFi\fedora\ - Not Found"?
____________________________________________
The error "Failed to open \EFI\fedora\ - Not Found" during EFI boot on Fedora Linux, especially from version 39 onwards, is typically related to some changes in how Fedora manages the bootloader and kernel entries on the EFI partition.
The main changes and potential reasons for this error include:
Migration to Boot Loader Specification (BLS) as Standard
Fedora has been gradually transitioning to using the Boot Loader Specification (BLS) to manage kernel entries. Previously, GRUB entries (grub.cfg) were generated in a more "static" way, and kernels were primarily stored in /boot.
With BLS, entries for each kernel are separate files (usually in /boot/loader/entries/ or similar directories), and GRUB reads them dynamically. The goal is to make the kernel update process more robust and less prone to errors in GRUB configuration.
How this causes the error: If for some reason GRUB cannot correctly read these BLS entries, or if the expected files on the EFI partition (like shimx64.efi or grubx64.efi and their respective configuration or entry files) are not in the expected location or are corrupted, it might fail to find what it needs to boot Fedora.
Changes in Kernel and Boot File Locations
There have been reports that, after upgrading to Fedora 39, new kernel versions might be stored directly in /boot/efi instead of /boot in some cases, which can confuse GRUB if it's looking elsewhere. This seems to be a specific behavior that can occur in certain configurations or with upgrade histories.
The error "Failed to open \EFI\fedora\ - Not Found" suggests that the UEFI firmware is trying to find the fedora file (or subdirectory) within the EFI partition but either doesn't find it or cannot access it. This could be caused by:
EFI System Partition (ESP) corruption: The EFI partition might have become corrupted, making essential Fedora files inaccessible.
Incorrect EFI boot entry: The boot entry in the UEFI firmware (viewable with efibootmgr) might be pointing to a non-existent or incorrect location after an update or reinstallation.
Permission or mounting issues: While less common directly, if the EFI partition isn't mounted correctly during updates or if there are permission issues, the necessary files might not be written or updated to the correct location.
Secure Boot: In some cases, incorrect Secure Boot settings can prevent the shimx64.efi (which is signed) or grubx64.efi from booting if they are not properly chained or if the keys are not recognized. The Failed to open \EFI\fedora\ - Not Found error can indicate that even the initial loader (shim or grub) isn't being found.
Bootloader Management Improvements with bootupd (Planned for Future Versions, but May Influence)
Fedora is working on unifying bootloader updates using a tool like bootupd. This aims to make updates more secure and reliable by decoupling package installation (via RPM) from the actual updates in /boot and /boot/efi. Although these deeper changes are more targeted for Fedora 42 and beyond (phase 1), the groundwork for this transition may have already introduced subtleties in bootloader behavior.
In summary, the "Failed to open \EFI\fedora\ - Not Found" error after Fedora 39 can be attributed to:
Problems with the EFI System Partition (ESP) itself, such as file system corruption or lack of space.
Outdated or incorrect UEFI boot entries that don't point to the correct location of the Fedora bootloader on the ESP.
Consequences of the transition to the Boot Loader Specification (BLS), where expectations about the location and format of boot files may have changed and are not always handled perfectly in all update scenarios.
Specific kernel update issues that fail to place new boot entries in the expected locations.
To diagnose and resolve this problem, you will typically need to:
Check the EFI partition: Mount it and verify the contents of the EFI/fedora directory (and EFI/BOOT if present).
Verify UEFI boot entries: Use the efibootmgr command (from a live CD/USB) to see existing boot entries and ensure there's a correct one for Fedora.
Reinstall GRUB/SHIM: This usually fixes issues with missing or corrupted files on the EFI partition.
These changes aim to improve the long-term robustness of the boot system, but like any transition, they can present challenges in specific user scenarios.
Ask part second mode (direct in english):
What changed in efi boot in Fedora Linux versions after version 39 that can cause the error "Failed to open \EFi\fedora\ - Not Found"?
_____________________________________________
The error "Failed to open \EFI\fedora\ - Not Found" after Fedora 39, particularly seen in Fedora 41 and 42, often points to issues related to the EFI System Partition (ESP) and how Fedora's bootloader (GRUB2 and shim) interacts with it. While there isn't a single "breaking change" after F39 that always causes this, several factors and common issues that become more prominent in later versions can lead to this error:
Space Issues on the EFI System Partition (/boot/efi):
One of the most frequently reported problems in Fedora versions, including 39, 40, and later, is the /boot/efi partition running out of space. This can happen especially on systems that have been upgraded through many Fedora releases.
New kernel installations and updates write files to /boot/efi/EFI/fedora/ and other directories within the ESP. If there's insufficient space, these files might not be written completely or correctly, leading to the bootloader not finding the necessary files.
Fedora 39 and later new installations typically create a larger ESP (around 600 MB) than older versions, but continuously upgrading from older installations can leave a smaller, easily filled ESP.
How it relates to the error: If shimx64.efi, grubx64.efi, or other crucial boot files in /EFI/fedora/ cannot be written due to lack of space, the UEFI firmware won't be able to find them, resulting in the "Not Found" error.
Changes in Kernel Installation Layout (kernel-install):
Fedora uses kernel-install to manage kernel installations and entries. There have been instances where the KERNEL_INSTALL_LAYOUT setting (e.g., bls vs. other) can cause issues. If this is misconfigured (or if an old configuration persists through upgrades), new kernel entries might not be created correctly in the EFI partition or might be placed in unexpected locations.
While not a direct "change after F39," the persistence of old or incorrect configurations from previous Fedora versions can manifest as issues in later releases like 41 and 42.
Multiple EFI System Partitions (ESPs) or Dual-booting:
When dual-booting with Windows or other Linux distributions, especially if each OS has its own ESP on different drives, the UEFI firmware might get confused or the boot order might be inadvertently changed.
The "Failed to open \EFI\fedora\ - Not Found" message can appear if the UEFI firmware is attempting to boot from an incorrect ESP or if the Fedora boot entry in the firmware's NVRAM points to a location that no longer contains the necessary files (e.g., after a reinstallation or partition change).
UEFI Firmware Quirks and Updates:
Some UEFI firmwares can be finicky. A firmware update (or even a bug in the existing firmware) can sometimes reset boot entries, change boot order, or have issues with certain EFI file paths, leading to the "Not Found" error.
In some cases, users have reported that certain motherboard models or UEFI firmware versions might struggle more with specific Fedora releases.
Corrupt or Missing EFI Files:
Beyond space issues, the EFI files themselves (shim, GRUB2, etc.) within the /boot/efi/EFI/fedora/ directory might become corrupted or accidentally deleted. This could be due to a failed update, a manual misconfiguration, or even a hardware issue.
Troubleshooting Steps (and what often helps):
Check ESP Space:
df -h /boot/efi to see if your EFI partition is full. If it is, you'll need to clean up old kernel entries from /boot/efi/EFI/fedora/ (being careful not to remove the currently booting kernel).
Verify EFI Boot Entries:
Use efibootmgr -v to check the UEFI boot entries and ensure that the Fedora entry points to the correct EFI file (usually \EFI\fedora\shimx64.efi or \EFI\fedora\grubx64.efi). You might need to re-add or reorder entries.
Reinstall GRUB2 and Shim:
Boot from a Fedora Live USB.
Mount your root and EFI partitions.
Chroot into your installed system.
Reinstall grub2-efi-x64 and shim-x64 packages, and then run grub2-mkconfig -o /boot/grub2/grub.cfg to regenerate the GRUB configuration.
Check kernel-install Layout:
Inspect /usr/lib/kernel/install.conf and /etc/kernel/install.conf to ensure layout=bls is set correctly if you are using the Boot Loader Specification.
Update BIOS/UEFI Firmware:
Ensure your motherboard's firmware is up to date, as this can often resolve compatibility issues.
In summary, the "Failed to open \EFI\fedora\ - Not Found" error in Fedora versions after 39 isn't typically due to a single, explicit change in how EFI boots, but rather a combination of factors that can lead to the EFI boot files becoming inaccessible or incorrect, with ESP space being a very common culprit in continuously upgraded systems.
I think to left the things as is, waiting the changes and opts what to do.