Hi all !
Hoping someone can suggest a fix or point me in an appropriate direction.
A week or so ago, I noticed a black horizontal line in the upper LEFT of my laptop. it is not a smudge on the monitor.

My specs are:
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Code: [Select]System: Kernel: 5.4.0-81-generic x86_64 bits: 64 compiler: gcc v: 9.3.0 Desktop: Cinnamon 4.8.6
wm: muffin dm: LightDM Distro: Linux Mint 20.1 Ulyssa base: Ubuntu 20.04 focal
MACHINE: Type: Laptop System: Hewlett-Packard product: HP 15 Notebook PC
v: 0974120000405F00000620180 serial: <filter> Chassis: type: 10 serial: <filter>
Mobo: Hewlett-Packard model: 2211 v: 86.45 serial: <filter> UEFI: Insyde v: F.32
date: 10/28/2014
Battery: ID-1: BAT1 charge: 29.5 Wh condition: 29.5/29.5 Wh (100%) volts: 16.7/14.8
model: 13-42 OA04041 serial: <filter> status: Full
CPU: Topology: Dual Core model: Intel Core i3-4005U bits: 64 type: MT MCP arch: Haswell
rev: 1 L2 cache: 3072 KiB
flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 13569
Speed: 851 MHz min/max: 800/1700 MHz Core speeds (MHz): 1: 869 2: 883 3: 872 4: 847
Graphics: Device-1: Intel Haswell-ULT Integrated Graphics vendor: Hewlett-Packard driver: i915
v: kernel bus ID: 00:02.0 chip ID: 8086:0a16
Display: x11 server: X.Org 1.20.11 driver: modesetting unloaded: fbdev,vesa
resolution: 1366x768~60Hz
OpenGL: renderer: Mesa DRI Intel HD Graphics 4400 (HSW GT2) v: 4.5 Mesa 21.0.3
compat-v: 3.0 direct render: Yes
Sensors: System Temperatures: cpu: 43.0 C mobo: 43.0 C
Fan Speeds (RPM): N/A
The line seems to be getting longer horizontally.
I've attached a scree and since I'm not CERTAIN it is not soft of firmware, I've posted this query in software as well there.

Thanks very much for any assistance! It's a rather old one so it might be physical problem with display. The crystals sometimes GET leaked inside and there you have that black line. IMHO.
Or, you can update the graphic driver or plug in another display to see if there is a black line also there. But, I thinks it's faulty display...