Problems with text rendering & black screen after the screen lock

Hi there.
I reinstalled Manjaro KDE because I was having some problems.
Now I am having different problems. Texts in settings menu are sometimes distorted, especially when I’m scrolling thru the menu.
See the text in the left side of the window.

Text rendering is not the only problem however. Wayland-session is acting weird generally. I’m experiencing some bugs&stuff. And the biggest one is this: After I enter my password in the lock screen, screen stays black. I can see my cursor, I can move it. After like 10-15 seconds, my desktop & panels & wallpaper becomes visible.

I am using video-linux driver and OpenGL 3.1. But it is the same with OpenGL 2.0 too.

System:
  Kernel: 5.15.19-1-MANJARO x86_64 bits: 64 compiler: gcc v: 11.1.0
    parameters: BOOT_IMAGE=/boot/vmlinuz-5.15-x86_64
    root=UUID=c93def77-6fc1-4dcc-8258-e43679fbfb4a rw quiet
    resume=UUID=fec6d4e2-394a-4cd7-a31a-b240dc9b55c0 udev.log_priority=3
  Desktop: KDE Plasma 5.23.5 tk: Qt 5.15.2 wm: kwin_wayland vt: 2 dm: SDDM
    Distro: Manjaro Linux base: Arch Linux
Machine:
  Type: Laptop System: Apple product: MacBookAir6,2 v: 1.0
    serial: <superuser required> Chassis: type: 10 v: Mac-7DF21CB3ED6977E5
    serial: <superuser required>
  Mobo: Apple model: Mac-7DF21CB3ED6977E5 v: MacBookAir6,2
    serial: <superuser required> UEFI: Apple v: 122.0.0.0.0 date: 06/10/2020
Battery:
  ID-1: BAT0 charge: 21.2 Wh (62.0%) condition: 34.2/54.3 Wh (62.9%)
    volts: 7.4 min: 7.6 model: SMP bq20z451 type: Li-ion serial: N/A
    status: Discharging cycles: 2684
Memory:
  RAM: total: 3.77 GiB used: 2.77 GiB (73.4%)
  RAM Report:
    permissions: Unable to run dmidecode. Root privileges required.
CPU:
  Info: model: Intel Core i5-4250U bits: 64 type: MT MCP arch: Haswell
    family: 6 model-id: 0x45 (69) stepping: 1 microcode: 0x26
  Topology: cpus: 1x cores: 2 tpc: 2 threads: 4 smt: enabled cache:
    L1: 128 KiB desc: d-2x32 KiB; i-2x32 KiB L2: 512 KiB desc: 2x256 KiB
    L3: 3 MiB desc: 1x3 MiB
  Speed (MHz): avg: 1317 high: 1352 min/max: 800/2600 scaling:
    driver: intel_cpufreq governor: schedutil cores: 1: 1352 2: 1300 3: 1316
    4: 1300 bogomips: 15207
  Flags: abm acpi aes aperfmperf apic arat arch_perfmon avx avx2 bmi1 bmi2
    bts clflush cmov constant_tsc cpuid cpuid_fault cx16 cx8 de ds_cpl dtes64
    dtherm dts epb ept ept_ad erms est f16c flexpriority flush_l1d fma fpu
    fsgsbase fxsr ht ibpb ibrs ida invpcid invpcid_single lahf_lm lm mca mce
    md_clear mmx monitor movbe msr mtrr nonstop_tsc nopl nx pae pat pbe pcid
    pclmulqdq pdcm pdpe1gb pebs pge pln pni popcnt pse pse36 pti pts rdrand
    rdtscp rep_good sdbg sep smep ss ssbd sse sse2 sse4_1 sse4_2 ssse3 stibp
    syscall tm tm2 tpr_shadow tsc tsc_adjust tsc_deadline_timer vme vmx vnmi
    vpid x2apic xsave xsaveopt xtopology xtpr
  Vulnerabilities:
  Type: itlb_multihit status: KVM: VMX disabled
  Type: l1tf
    mitigation: PTE Inversion; VMX: conditional cache flushes, SMT vulnerable
  Type: mds mitigation: Clear CPU buffers; SMT vulnerable
  Type: meltdown mitigation: PTI
  Type: spec_store_bypass
    mitigation: Speculative Store Bypass disabled via prctl and seccomp
  Type: spectre_v1
    mitigation: usercopy/swapgs barriers and __user pointer sanitization
  Type: spectre_v2 mitigation: Full generic retpoline, IBPB: conditional,
    IBRS_FW, STIBP: conditional, RSB filling
  Type: srbds mitigation: Microcode
  Type: tsx_async_abort status: Not affected
Graphics:
  Device-1: Intel Haswell-ULT Integrated Graphics vendor: Apple driver: i915
    v: kernel bus-ID: 00:02.0 chip-ID: 8086:0a26 class-ID: 0300
  Display: wayland server: X.org 1.21.1.3 compositor: kwin_wayland driver:
    loaded: modesetting alternate: fbdev,vesa display-ID: 0
    resolution: <missing: xdpyinfo>
  Message: Unable to show advanced data. Required tool glxinfo missing.
Audio:
  Device-1: Intel Haswell-ULT HD Audio vendor: Apple driver: snd_hda_intel
    v: kernel bus-ID: 00:03.0 chip-ID: 8086:0a0c class-ID: 0403
  Device-2: Intel 8 Series HD Audio driver: snd_hda_intel v: kernel
    bus-ID: 00:1b.0 chip-ID: 8086:9c20 class-ID: 0403
  Device-3: Broadcom 720p FaceTime HD Camera driver: facetimehd v: kernel
    bus-ID: 02:00.0 chip-ID: 14e4:1570 class-ID: 0480
  Sound Server-1: ALSA v: k5.15.19-1-MANJARO running: yes
  Sound Server-2: JACK v: 1.9.20 running: no
  Sound Server-3: PulseAudio v: 15.0 running: yes
  Sound Server-4: PipeWire v: 0.3.45 running: yes
Network:
  Device-1: Broadcom BCM4360 802.11ac Wireless Network Adapter vendor: Apple
    driver: wl v: kernel modules: bcma bus-ID: 03:00.0 chip-ID: 14e4:43a0
    class-ID: 0280
  IF: wlp3s0 state: up mac: <filter>
  IP v4: <filter> type: dynamic noprefixroute scope: global
    broadcast: <filter>
  IP v6: <filter> type: noprefixroute scope: link
  WAN IP: <filter>
Bluetooth:
  Device-1: Apple Bluetooth USB Host Controller type: USB driver: btusb v: 0.8
    bus-ID: 1-3.3:6 chip-ID: 05ac:828f class-ID: fe01
  Report: rfkill ID: hci0 rfk-id: 0 state: down bt-service: enabled,running
    rfk-block: hardware: no software: yes address: see --recommends
Logical:
  Message: No logical block device data found.
RAID:
  Message: No RAID data found.
Drives:
  Local Storage: total: 113 GiB used: 43.47 GiB (38.5%)
  SMART Message: Unable to run smartctl. Root privileges required.
  ID-1: /dev/sda maj-min: 8:0 vendor: Apple model: SSD SM0128F size: 113 GiB
    block-size: physical: 4096 B logical: 512 B speed: 6.0 Gb/s type: SSD
    serial: <filter> rev: EA1Q scheme: GPT
  Message: No optical or floppy data found.
Partition:
  ID-1: / raw-size: 104.4 GiB size: 102.2 GiB (97.89%) used: 42.75 GiB (41.8%)
    fs: ext4 dev: /dev/sda2 maj-min: 8:2 label: N/A
    uuid: c93def77-6fc1-4dcc-8258-e43679fbfb4a
  ID-2: /boot/efi raw-size: 300 MiB size: 299.4 MiB (99.80%)
    used: 288 KiB (0.1%) fs: vfat dev: /dev/sda1 maj-min: 8:1 label: NO_LABEL
    uuid: 7947-A556
Swap:
  Kernel: swappiness: 60 (default) cache-pressure: 100 (default)
  ID-1: swap-1 type: partition size: 8.3 GiB used: 736.2 MiB (8.7%)
    priority: -2 dev: /dev/sda3 maj-min: 8:3 label: swap
    uuid: fec6d4e2-394a-4cd7-a31a-b240dc9b55c0
Unmounted:
  Message: No unmounted partitions found.
USB:
  Hub-1: 1-0:1 info: Hi-speed hub with single TT ports: 9 rev: 2.0
    speed: 480 Mb/s chip-ID: 1d6b:0002 class-ID: 0900
  Hub-2: 1-3:2
    info: Broadcom BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth) ports: 3
    rev: 2.0 speed: 12 Mb/s power: 94mA chip-ID: 0a5c:4500 class-ID: 0900
  Device-1: 1-3.3:6 info: Apple Bluetooth USB Host Controller
    type: Bluetooth driver: btusb interfaces: 4 rev: 2.0 speed: 12 Mb/s
    chip-ID: 05ac:828f class-ID: fe01
  Device-2: 1-5:3 info: Apple Apple Internal Keyboard / Trackpad
    type: HID,Keyboard,Mouse driver: apple,bcm5974,usbhid interfaces: 3 rev: 2.0
    speed: 12 Mb/s power: 500mA chip-ID: 05ac:0291 class-ID: 0301
    serial: <filter>
  Hub-3: 2-0:1 info: Super-speed hub ports: 4 rev: 3.0 speed: 5 Gb/s
    chip-ID: 1d6b:0003 class-ID: 0900
  Device-1: 2-3:2 info: Apple Internal Memory Card Reader type: Mass Storage
    driver: usb-storage interfaces: 1 rev: 3.0 speed: 5 Gb/s power: 896mA
    chip-ID: 05ac:8406 class-ID: 0806 serial: <filter>
Sensors:
  System Temperatures: cpu: 65.0 C mobo: N/A
  Fan Speeds (RPM): N/A
Info:
  Processes: 224 Uptime: 1h 10m wakeups: 2 Init: systemd v: 250
  tool: systemctl Compilers: gcc: 11.1.0 clang: 13.0.0 Packages: 1388
  pacman: 1380 lib: 358 flatpak: 8 Shell: Zsh v: 5.8 running-in: yakuake
  inxi: 3.3.12