@Tortletalk
I've copied this from the guide on page 1:
"
This is due to your NW JS version having been changed at one point and then changed again after that. This is actually on your system and reinstalling/deleting the game won't fix it as the problem persists in your appdata, especially if you play multiple RPG Maker games by multiple people it may cause this if people play around with NW JS files.
- To fix this error click your file explorer and type in
%LOCALAPPDATA%/ (You can also go to users/*your user name*/Appdata/Local to achieve same effect)
- Then go into KADOKAWA\RPGMV\User Data\Default
- Delete both Web Data and Web Data-journal.
After this the NW JS gets updated when the game is ran again and the error will disappear.
"
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I finally got around playing with this to see how it performs, and pretty much immediately stumbled on two issues which make me question if upgrading is really a viable option. I am at this point assuming that these are not only happening to me, but if you have a different experience or solution, feel free to answer.
First off: As soon as you replace the nw.js application, you will get blocked by Windows Defender when trying to start your game for the first time. The reason being that it is not signatured.
I normally do not care about these blocks too much, as you will run into them eventually when you play games from other sites. That being said, other players may raise an eyebrow if they start your rpg maker game and get this notification. If we go the publishing on Steam route, it becomes especially... problematic.
Second: The nw.js profile error. I had at first assumed that it may be bound to a specific game, but from what I can see it is bound to the specific engine used. So in this case either MV or MZ. The problem here is that even if you resolve the issue for your project, if a player starts another game of the same engine, they will run into the same issue once more as soon as that game has a lower nw.js version than yours. At the end of the day, this is of course technically not your problem - as long as you don't end up on the other side of the table.
I looked over the pages of this guide and it seems there may be a solution to assigning your project a specified path, maybe solving that issue. In another thread however I read that especially MZ seems to overwrite that specific .json file everytime the game runs or is saved (... something like that).
As long as these issues persist (again, gladly prove me wrong if you can), I do not see an (objective) merit that makes this worth unquestionable.
From what I understand, this greatly boosts the performance for MV. So if these issues are of no concern for someone specifically, it seems like a possible trade. A trade with (subjective) drawbacks, though.
For MZ, as far as I could see in my project: It did stabilize the framerate somewhat, but if I had a stronger system, it wouldn't even matter.
Again, this is for my project, though - with some plugins which cost me about 10 fps and cause occasional lag spikes on my small test map. Could probably get a bit worse when filling an entire larger map, but runs without problems in vanilla and better in performance mode of my system. So in short: If I would not have hardware that not quite matches the software's minimum requirements, I would probably get a solid 60 without any problems.
The same goes for pixi.js, by the way. It gave me a solid (small) improvement, personally, but it may or may not matter to you. That being said, pixi.js has no problems like nw.js, it is rather a matter of not being able to upgrade it much further without compatibility issues.
The devs left it on the last 5.x version for a reason. I could only go as far as 6.0.4 as everything from 6.1 onwards changed too much, immediately giving me a crash on startup. I believe 6.5? did work for some reason, but I had issues with one of the plugins I use, basically displaying the tileset improperly.
So in short: Both viable upgrades, especially for MV I presume. Because at the end of the day you will always try to stabilize your framerate as much as possible.
But the problems that come with upgrading nw.js manually do raise some concerns. As I do not plan to upload my game anywhere 'steam-like', I could probably just live with the Defender Notification and say "if you play other games made with mz I do not care", but... well.
Then again, if "everyone" upgrades their nw.js in all versions possible, I wonder if I should actually even care at this point.
So going from there, I guess I just wanted to put that out there. I am not quite sure how I should decide personally at the moment, so I will think this over. Or - again - maybe someone knows better than me.