Disclaimer: I know this is similar to a previous question I asked that is related to this issue, but it was a bit too specific, and I've decided to ask a more general/focused question this time in the hopes of getting a concise/working answer.
I recently noticed that a major issue arises when trying to use datapacks from the website Vanilla Tweaks (a website that hosts a multitude of datapacks that add small changes to the normal minecraft vanilla experience, hence the name - they're mostly rather small datapacks that aren't game-changing - more like plugins rather than mods.) on a specific 1.14 world (what I mean is not one specific world, but rather a world that has unique modifiers to it - in this case, it was converted from 1 version to another).
I didn't want to make the title any more confusing, but I still wanted to address that this is not a normal 1.14 world ("normal" meaning any sort of world that was created while playing in vanilla 1.14 and nothing else), but rather has these modifiers:
The world was created in vanilla 1.8.9. (meaning this would be a "normal" 1.8.9 world, in a sense)
No world settings were changed, other than setting the default gamemode to Creative Mode (which automatically enabled cheats) and changing the seed (normal world type, no additional changes).
The seed used was "StackExchange" (just as a test seed). Numerical seed is 655809707.
After creating the world, the world was converted to minecraft version 1.14.4 (vanilla) with no other alterations. (this was done by saving/quitting the world, relogging with ver. vanilla 1.14.4, and then joining into the world again)
After doing this, I then installed a datapack that required a /trigger command to use (essentially forcing the player to do /trigger [objective in datapack] in order to actually enable the datapack and/or toggle settings), and when entering /trigger, there were no objectives listed.
The datapack was recognized by minecraft itself, as it was shown in /datapack list.
I know that this was not supposed to happen, as after making a normal 1.14 world and applying the exact same settings and the exact same datapack, the /trigger command for the specific datapack was working perfectly fine.
I had also converted a world from 1.12.2 to 1.14.4, and /trigger commands were also working fine.
So, I can only think that there is some issue that occurs when converting a 1.8 world into 1.13 or higher (since it wasn't working for 1.14, I can assume that it would also not work for 1.13). My question is, is there a way to fix this issue on a world that was already converted from 1.8 to 1.13+?
It might be nice to also know a way to prevent this issue from occuring before converting a world, but I already have a rather-developed world that has this issue (which was converted from 1.8 to 1.14), and I hopefully want to find a way to make it so I can still use datapacks on that world. Thank you, and I appreciate any help I can get!
Link to VanillaTweaks datapacks (datapack I used was Coordinates HUD, for 1.14): https://vanillatweaks.net/picker/datapacks/
The world before converting to 1.14.4 (world version - 1.8.9): https://www.mediafire.com/file/8p1emc348isw0v6/file
The world after converting to 1.14.4, includes mentioned datapack (world version - 1.14.4): https://www.mediafire.com/file/jr2z8mcgywlx80v/file