[Paid Software Announcement and Discussion] KaMyKaSii:
No, my device has partitions listed by names. FlashFire recognizes the partitions without any workaround or something. In roms based on Lollipop, FlashFire worked perfectly (until the time I used it). In Marshmallow it rarely worked but mostly not. And my device does not have the /proc/dumchar_info file. Below is the contents of my /dev/block, informe me of any other information you may need.

/dev/block/:
total 0
drwxr-xr-x 4 0 0 840 Apr 1 03:39 .
drwxr-xr-x 15 0 0 3340 Apr 1 03:39 ..
brw------- 1 0 0 7, 0 Apr 1 03:39 loop0
brw------- 1 0 0 7, 1 Apr 1 03:39 loop1
brw------- 1 0 0 7, 2 Apr 1 03:39 loop2
brw------- 1 0 0 7, 3 Apr 1 03:39 loop3
brw------- 1 0 0 7, 4 Apr 1 03:39 loop4
brw------- 1 0 0 7, 5 Apr 1 03:39 loop5
brw------- 1 0 0 7, 6 Apr 1 03:39 loop6
brw------- 1 0 0 7, 7 Apr 1 03:39 loop7
brw-rw---- 1 0 1000 179, 0 Apr 1 03:39 mmcblk0
brw-rw---- 1 0 1000 179, 32 Apr 1 03:39 mmcblk0boot0
brw-rw---- 1 0 1000 179, 64 Apr 1 03:39 mmcblk0boot1
brw-rw---- 1 0 1000 179, 1 Apr 1 03:39 mmcblk0p1
brw------- 1 0 0 179, 10 Apr 1 03:39 mmcblk0p10
brw-rw---- 1 0 1000 179, 11 Apr 1 03:39 mmcblk0p11
brw------- 1 0 0 179, 12 Apr 1 03:39 mmcblk0p12
brw-r----- 1 0 1000 179, 13 Apr 1 03:39 mmcblk0p13
brw------- 1 0 0 179, 14 Apr 1 03:39 mmcblk0p14
brw------- 1 0 0 179, 15 Apr 1 03:39 mmcblk0p15
brw------- 1 0 0 179, 16 Apr 1 03:39 mmcblk0p16
brw-rw---- 1 0 1000 179, 17 Apr 1 03:42 mmcblk0p17
brw------- 1 0 0 179, 18 Apr 1 03:39 mmcblk0p18
brw------- 1 0 0 179, 19 Apr 1 03:39 mmcblk0p19
brw-rw---- 1 0 1000 179, 2 Apr 1 03:39 mmcblk0p2
brw------- 1 0 0 179, 20 Apr 1 03:39 mmcblk0p20
brw------- 1 0 0 179, 21 Apr 1 03:39 mmcblk0p21
brw------- 1 0 0 179, 22 Apr 1 03:39 mmcblk0p22
brw------- 1 0 0 179, 23 Apr 1 03:39 mmcblk0p23
brw------- 1 0 0 179, 3 Apr 1 03:39 mmcblk0p3
brw------- 1 0 0 179, 4 Apr 1 03:39 mmcblk0p4
brw------- 1 0 0 179, 5 Apr 1 03:39 mmcblk0p5
brw-rw---- 1 0 1000 179, 6 Apr 1 03:39 mmcblk0p6
brw-r----- 1 0 1000 179, 7 Apr 1 03:39 mmcblk0p7
brw-r----- 1 0 1000 179, 8 Apr 1 03:39 mmcblk0p8
brw-rw---- 1 0 1000 179, 9 Apr 1 03:39 mmcblk0p9
brw------- 1 0 0 179, 96 Apr 1 03:39 mmcblk0rpmb
brw------- 1 0 0 179, 128 Apr 1 03:39 mmcblk1
brw------- 1 0 0 179, 129 Apr 1 03:39 mmcblk1p1
drwxr-xr-x 3 0 0 60 Apr 1 03:39 platform
drwx------ 2 0 0 80 Apr 1 03:40 vold
brw------- 1 0 0 254, 0 Apr 1 03:39 zram0

/dev/block/platform:
total 0
drwxr-xr-x 3 0 0 60 Apr 1 03:39 .
drwxr-xr-x 4 0 0 840 Apr 1 03:39 ..
drwxr-xr-x 4 0 0 80 Apr 1 03:39 mtk-msdc.0

/dev/block/platform/mtk-msdc.0:
total 0
drwxr-xr-x 4 0 0 80 Apr 1 03:39 .
drwxr-xr-x 3 0 0 60 Apr 1 03:39 ..
drwxr-xr-x 4 0 0 620 Apr 1 03:39 11230000.msdc0
drwxr-xr-x 3 0 0 100 Apr 1 03:39 11240000.msdc1

/dev/block/platform/mtk-msdc.0/11230000.msdc0:
total 0
drwxr-xr-x 4 0 0 620 Apr 1 03:39 .
drwxr-xr-x 4 0 0 80 Apr 1 03:39 ..
drwxr-xr-x 2 0 0 500 Apr 1 03:39 by-name
drwxr-xr-x 2 0 0 500 Apr 1 03:39 by-num
lrwxrwxrwx 1 0 0 18 Apr 1 03:39 mmcblk0 -> /dev/block/mmcblk0
lrwxrwxrwx 1 0 0 23 Apr 1 03:39 mmcblk0boot0 -> /dev/block/mmcblk0boot0
lrwxrwxrwx 1 0 0 23 Apr 1 03:39 mmcblk0boot1 -> /dev/block/mmcblk0boot1
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk0p1 -> /dev/block/mmcblk0p1
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p10 -> /dev/block/mmcblk0p10
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p11 -> /dev/block/mmcblk0p11
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p12 -> /dev/block/mmcblk0p12
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p13 -> /dev/block/mmcblk0p13
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p14 -> /dev/block/mmcblk0p14
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p15 -> /dev/block/mmcblk0p15
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p16 -> /dev/block/mmcblk0p16
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p17 -> /dev/block/mmcblk0p17
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p18 -> /dev/block/mmcblk0p18
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p19 -> /dev/block/mmcblk0p19
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk0p2 -> /dev/block/mmcblk0p2
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p20 -> /dev/block/mmcblk0p20
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p21 -> /dev/block/mmcblk0p21
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p22 -> /dev/block/mmcblk0p22
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 mmcblk0p23 -> /dev/block/mmcblk0p23
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk0p3 -> /dev/block/mmcblk0p3
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk0p4 -> /dev/block/mmcblk0p4
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk0p5 -> /dev/block/mmcblk0p5
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk0p6 -> /dev/block/mmcblk0p6
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk0p7 -> /dev/block/mmcblk0p7
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk0p8 -> /dev/block/mmcblk0p8
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk0p9 -> /dev/block/mmcblk0p9
lrwxrwxrwx 1 0 0 22 Apr 1 03:39 mmcblk0rpmb -> /dev/block/mmcblk0rpmb

/dev/block/platform/mtk-msdc.0/11230000.msdc0/by-name:
total 0
drwxr-xr-x 2 0 0 500 Apr 1 03:39 .
drwxr-xr-x 4 0 0 620 Apr 1 03:39 ..
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 boot -> /dev/block/mmcblk0p7
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 cache -> /dev/block/mmcblk0p21
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 expdb -> /dev/block/mmcblk0p10
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 flashinfo -> /dev/block/mmcblk0p23
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 frp -> /dev/block/mmcblk0p17
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 keystore -> /dev/block/mmcblk0p14
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 lk -> /dev/block/mmcblk0p5
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 logo -> /dev/block/mmcblk0p9
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 metadata -> /dev/block/mmcblk0p19
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 nvdata -> /dev/block/mmcblk0p18
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 nvram -> /dev/block/mmcblk0p2
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 oemkeystore -> /dev/block/mmcblk0p12
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 para -> /dev/block/mmcblk0p6
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 proinfo -> /dev/block/mmcblk0p1
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 protect1 -> /dev/block/mmcblk0p3
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 protect2 -> /dev/block/mmcblk0p4
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 recovery -> /dev/block/mmcblk0p8
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 seccfg -> /dev/block/mmcblk0p11
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 secro -> /dev/block/mmcblk0p13
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 system -> /dev/block/mmcblk0p20
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 tee1 -> /dev/block/mmcblk0p15
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 tee2 -> /dev/block/mmcblk0p16
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 userdata -> /dev/block/mmcblk0p22

/dev/block/platform/mtk-msdc.0/11230000.msdc0/by-num:
total 0
drwxr-xr-x 2 0 0 500 Apr 1 03:39 .
drwxr-xr-x 4 0 0 620 Apr 1 03:39 ..
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p1 -> /dev/block/mmcblk0p1
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p10 -> /dev/block/mmcblk0p10
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p11 -> /dev/block/mmcblk0p11
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p12 -> /dev/block/mmcblk0p12
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p13 -> /dev/block/mmcblk0p13
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p14 -> /dev/block/mmcblk0p14
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p15 -> /dev/block/mmcblk0p15
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p16 -> /dev/block/mmcblk0p16
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p17 -> /dev/block/mmcblk0p17
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p18 -> /dev/block/mmcblk0p18
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p19 -> /dev/block/mmcblk0p19
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p2 -> /dev/block/mmcblk0p2
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p20 -> /dev/block/mmcblk0p20
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p21 -> /dev/block/mmcblk0p21
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p22 -> /dev/block/mmcblk0p22
lrwxrwxrwx 1 0 0 21 Apr 1 03:39 p23 -> /dev/block/mmcblk0p23
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p3 -> /dev/block/mmcblk0p3
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p4 -> /dev/block/mmcblk0p4
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p5 -> /dev/block/mmcblk0p5
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p6 -> /dev/block/mmcblk0p6
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p7 -> /dev/block/mmcblk0p7
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p8 -> /dev/block/mmcblk0p8
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p9 -> /dev/block/mmcblk0p9

/dev/block/platform/mtk-msdc.0/11240000.msdc1:
total 0
drwxr-xr-x 3 0 0 100 Apr 1 03:39 .
drwxr-xr-x 4 0 0 80 Apr 1 03:39 ..
drwxr-xr-x 2 0 0 60 Apr 1 03:39 by-num
lrwxrwxrwx 1 0 0 18 Apr 1 03:39 mmcblk1 -> /dev/block/mmcblk1
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 mmcblk1p1 -> /dev/block/mmcblk1p1

/dev/block/platform/mtk-msdc.0/11240000.msdc1/by-num:
total 0
drwxr-xr-x 2 0 0 60 Apr 1 03:39 .
drwxr-xr-x 3 0 0 100 Apr 1 03:39 ..
lrwxrwxrwx 1 0 0 20 Apr 1 03:39 p1 -> /dev/block/mmcblk1p1

/dev/block/vold:
total 0
drwx------ 2 0 0 80 Apr 1 03:40 .
drwxr-xr-x 4 0 0 840 Apr 1 03:39 ..
brw------- 1 0 0 179, 128 Apr 1 03:39 disk:179,128
brw------- 1 0 0 179, 129 Apr 1 03:40 public:179,129

Useless information for the black screen case but maybe important for compatibility with by-num devices:

There are two variants of my device: one with MT6753 arm64, which I have. And one with MT6592M armv-7. The second one does have the /proc/dumchar_info file but it did not have its partitions recognized by FlashFire (since it is not a by-name device). As another user pointed out [URL='https://xdaforums.com/general/paid-software/flashfire-t3075433/post70420203]here[/URL], you can make FlashFire recognize the main partitions (recovery, system, cache, data) by doing symlinks (like creating /dev/block/platform/by-name directory and then ln -s /dev/recovery /dev/block/platform/by-name/recovery). A friend tested this and the backup functions in FlashFire worked perfectly except for boot partition (/dev/bootimg)