Hey! If your LG phone screen shows lines (vertical lines, horizontal lines, or a single green line), we can narrow down what’s happening using safe, non-destructive checks only.

People describe “lines on the screen” in a few different ways, and the pattern matters:
• One thin green vertical line (often constant, edge-to-edge)
• Multiple vertical stripes (may come and go, sometimes after a drop/pressure)
• Horizontal lines + flickering (can look like refresh/glitching)
• Lines only in certain apps (camera, TikTok, games) vs everywhere

Quick triage — answer any you can, in any order:
1) What LG model? (G8/G7, V series, Velvet, Stylo, K series, etc.)
2) When did it start? After a drop, pressure in a pocket/bag, water/humidity, a new app, or an Android update?
3) Are the lines visible on the boot logo (LG logo) or only after Android loads?

That description helps a lot. A single straight green line that shows up “everywhere” (home screen + apps) is usually different from a temporary glitch — but we still don’t assume the worst until we collect a few clues.

The reason lines appear typically fits into one of these buckets:
• Display path (hardware): screen panel / display driver / flex connection reacting to pressure, impact, or internal wear.
• Rendering/overlay (software): a display setting, accessibility filter, screen overlay app, or graphics glitch that draws on top of the picture.
• Heat/moisture stress: less common, but can make a marginal display connection act up.

Before any steps: when you say “in my backpack,” do you mean it could’ve had pressure on the screen (books/laptop pushing on it)? And do you see the line at very low brightness and also at high brightness, or does it change?

“Brighter on dark backgrounds” is a common report with OLED/AMOLED line issues, but we’ll keep this evidence-based and safe.

Here are two quick checks that don’t risk your data and are useful for diagnosis (not “magic fixes”):
1) Screenshot test (important): Take a screenshot while the line is visible. Then view that screenshot on another device (or send it to a friend / open it on a computer).
• If the line appears in the screenshot image, that suggests a software/rendering/overlay problem.
• If the line is NOT in the screenshot, it points more toward the physical display path (panel/driver), because screenshots capture what the phone “thinks” it drew, not what the panel actually shows.

2) Boot/lock screen comparison: Do you see the line on the LG boot logo or in the lock screen before you open anything? Lines that appear before apps load are less likely to be caused by a specific app.

When you have a moment: can you tell me whether the line shows on the boot logo, and whether it shows in a screenshot viewed elsewhere?

That’s a strong diagnostic result: not in screenshots + visible on lock screen/early usually points away from a simple overlay/app and more toward the display hardware path (panel/driver/flex). It doesn’t automatically mean “your phone is dead,” but it does mean our safest goal is to check for risk factors and decide how urgent it is.

A few questions in a different order (because they change what I’d recommend next):
• Has the line changed over 24 hours? (thicker, more lines, flickering?)
• Any touch issues? For example, the screen looks fine except the line, but touch still works everywhere? Or is touch unresponsive near the line?
• Any moisture event? Steam, rain, bathroom humidity, spilled drink — even if it wasn’t “dropped in water.”

Also: if you use a case with a tight edge, it can sometimes put pressure on the display. As a test (not a fix), removing the case for a day can tell us if pressure is making it worse.

Your worry is reasonable — lines can stay stable for a long time, but they can also multiply if the underlying issue is pressure-related. The safest approach is: reduce stress on the display, gather a little more evidence, and avoid anything that could make it worse.

Here are safe checks that help you decide whether this is likely to stay “cosmetic” for now or whether it’s trending toward a repair need:
1) Case-off observation: Run it without the tight case for a while. Don’t press on the screen to “test” it — just observe whether the line flickers or changes during normal use.
2) Temperature check: If the phone gets unusually warm (gaming, charging), does the line change intensity or flicker? Heat can make a marginal display connection behave differently.
3) External display / casting check (if you can): If you cast the screen to a TV/monitor, the cast image typically won’t show panel defects. If the cast looks perfect while the phone screen shows a line, it supports “panel path” vs “software rendering.”

One more simple thing: do you have any screen filter / blue light / accessibility color apps enabled, or “Night Light” type settings? Those usually don’t create one razor-straight line, but it’s worth ruling out anything that draws on top of the display.

You’re right to pause there. Developer options tweaks can change how the phone renders graphics, and while they can help with some flickering or overlay issues, they’re not a good first move for a clean “single line” symptom — especially when the line doesn’t show in screenshots.

A safer, “Bing-friendly” diagnostic path is to do comparisons that don’t change system internals:
• Cast comparison: If the TV shows a normal picture while the phone shows a line, that strongly supports a screen/panel path issue rather than Android drawing it.
• Safe Mode check (diagnostic, not a repair): If you can boot into Safe Mode and the line remains exactly the same, that’s another hint it’s not caused by third-party apps or overlays.
• Rotate & UI check: Does the line stay in the same physical spot even when you rotate to landscape? If it stays in the same place on the glass, that’s more consistent with the panel rather than a UI element.

If you want, you can do just one simple test now: cast the screen and open a dark image (or a black background). Tell me whether the cast image has any line at all.

That’s a very clear comparison, and you handled it the right way. With no line in screenshots and no line on the cast, the evidence strongly points to the phone’s display panel / display driver path rather than software.

What you can do safely (without pretending there’s a “guaranteed fix”):
• Reduce pressure risk: keep it out of tight pockets/backpacks where the screen can flex; avoid sitting with it in a back pocket; use a case that doesn’t pinch the edges.
• Watch for escalation signs: more lines, flickering bands, or touch dead zones. If those appear, it’s more urgent to get it checked because the panel can degrade further.
• Back up important stuff: not because your data is in danger today, but because if the display worsens, it can become harder to use the phone normally.

If you’d like to keep diagnosing without risky steps, the next “safe” question is: do the lines show up in recovery/boot screens consistently, and do they ever disappear temporarily after the phone cools down? Those details help estimate whether it’s stable or trending.