Flashing LoRa v2.1‑1.6 fails – black screen, “invalid magic byte” on serial

[ipse-diabolus]

I’m trying to flash (web flasher) 2.7.1 onto a LoRa v2.1‑1.6 module (with 2.5.11), but it seems never flashs successfully. Suddenly, the display stays black, and the green STATUS LED stops blinking. I see this on the serial console:

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 188777542, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:2
load:0x3fff0030,len:1184
load:0x40078000,len:13192
load:0x40080400,len:3028
entry 0x400805e4
E (289) esp_core_dump_flash: No core �f~mp partition found!
E (289) esp_core_dump_flash: No core dump partition found!
E (197) psram: PSRAM ID read error: 0xffffffff

//\ E S H T /\ S T / C Failsafe OTA

ESP32 Chip model = 1
This chip has 240 MHz
Setting random seed 1511563909
Total heap: 255628
Free heap: 227996
Total PSRAM: 0
Free PSRAM: 0
NVS: UsedEntries 98, FreeEntries 532, AllEntries 630, NameSpaces 4
Number of Device Reboots: 90
Filesystem files (8192/1048576 Bytes):
E (239) esp_image: image at 0x10000 has invalid magic byte (nothing flashed here?)
[ 50][E][vfs_api.cpp:105] open(): /littlefs/prefs/db.proto does not exist, no permits for creation
No /prefs/db.proto preferences found
Hardware Model: 0
Main Firmware Version:
BLE name: *****
Waiting a client connection to notify...

What do I need to flash now, and how, or is it beyond saving?