Re - references to HDR on macrumors posts - this illustrates an interesting phenomenon.
This is a point of confusion by poster Cell-666.
The first post by Gigatoaster correctly points to a conflict with the Ultra HD Deep Color mode, which the screen cap shows. This feature is related to, but not the same as HDR, or High Dynamic Range.
Cell-666 then refers to the setting as HDR, conflating Ultra HD Deep Color with HDR, which is a misnomer.
The next poster then uses the same setting in the screen cap with success, but then adopts the same handle as Cell-666 to report it - HDR - instead of the correct moniker - Ultra HD Deep Color, or UDC.
The subsequent posters are changing the setting they saw in the screen cap, but calling it what cell-666 called it - HDR, instead of what it is - UDC.
With so many wrong references to HDR, readers who don’t take time to piece through the chronology won’t see where it goes wrong, and just try HDR, which doesn’t work, depriving them of the fix. It’s sort of like the childhood game of telephone, where serial coloring of a statement upends its meaning.
This is why when leveraging forum posts, some engineering logic is often needed to precisely discern the actual underlying cause from casual statements.
The real nuggets of truth were the jpg of the correct LG menu setting, from Gigatoaster, together with the confirmation from cell-666 and Shamhead that it worked. But you have to independently infer that the name he called it - HDR - was simply wrong.
User forums are fantastic tools to get community help, but casual comments can have errors in them. To leverage these reports, you must rely on very careful logic, and the discipline of scientific principles, (only believe what the data supports) to weigh the relevant facts and get to a core understanding.
In a process like treg, this logic-based approach has been used extensively to resolve edge case details. We may have an initial hunch about why something may occur, but we need to be open to other causes, and get solid data to corroborate the right resolution.
This logic really works, and is why the many contributions of treg users have produced a machine that performs well today.