There is no way I can imagine that the same jpg can one day be 'clean' & another day be 'grainy', then the next back to 'clean', unless it is being viewed by an app that is failing to correctly load it, or is re-interpreting at load.
The file itself is either good or it is broken. Broken files don't demonstrate 'grain' they either show large blocks of ...
In Adobe Photoshop, you can use this plugin from Exchange:
It is generally recommended to publish photos on the web in sRGB colour space. You have used the correct export setting.
Ideally you calibrate and profile your computer monitor. But this is a huge topic if you want to know all the details. It will be worth the effort if you earn money with photography or are doing prints and need soft-proofing.
The use of ...
Honestly, I am surprised you expect them to be the same! Screens are very different and in both cases you adjust them in a myriad of ways. Even assuming your screen is calibrated, your file will have the correct colors but any display can show them differently. If your display is not calibrated and even you are not seeing the actual colors!
My phone for ...
Those images have one thing in common. That is the warm color tone and also the neutral whites. Take a look at this image:
Did you ever see a gray sky like this? To achieve this look I would go to the HSL section in the develop tab in lightroom and set the saturation of cooler colors to a small value. I would not set them to 0 because then you ...
There is a readme.txt at both
C:\Program Files\Adobe\Adobe Lightroom Classic\Resources\LensProfiles\1.0\ThirdParty
Install third-party (non-Adobe) lens profiles here.
By default, .lcp files are saved to
I left ...