[TES4] Copy as overrides fails for MGEF

[MacSplody]

What is the version of xEdit you are using?

TES4Edit 4.0.3 (1CDF3AC7)

Describe the bug
When using "Copying as Override" on a MGEF record, an error message will show for an assertion. The record is created in the overriding module, but it has no content.

To reproduce
Steps to reproduce the behavior:
Go to Oblivion.esm (Or any module with MGEF records).
Right click any MGEF record and select copy as Override.
Target module can be new or existing plugin.
After hitting confirm, you'll then receive an error message.
Assertion failure (P:\TES5Edit\wbImplementation.pas, line 15543).
Open the newly created override record.
You should now see a record containing only the signature and formid.
The rest of its content will be empty.

Expected behavior
The new record should match the original record selected for "Copy as Override".

Screenshots

Additional context

Logs.zip

[MacSplody]

Just to add to this, if I make a new record.
The only sub records I can't add to are EDID - Magic Effect Code and ESCE - Counter Effects.

[ElminsterAU]

Oblivion does not support adding new MGEF. The only way for new MGEF is using OBME (oblivion magic extender). Such new MGEF are not identified by a 4 character EDID but with magic effects integer. So not being able to add an EDID to an MGEF record with OBME header is normal.

[MacSplody]

Oblivion does not support adding new MGEF. The only way for new MGEF is using OBME (oblivion magic extender). Such new MGEF are not identified by a 4 character EDID but with magic effects integer. So not being able to add an EDID to an MGEF record with OBME header is normal.

Could the user be prevented from trying to add new MGEF or informed of that limitation?

[ElminsterAU]

Well, xEdit DOES support OBME (at least it's supposed to), so adding new MGEF is supported. And your original issue is that copy as override doesn't work right, which I definitely need to look at.

[Infernio]

Probably related: when I copy as override any record that contains OBME info (tested with ALCH, ENCH and SPEL - haven't been able to find one with INGR or SGST yet), I get an access violation:
https://gist.github.com/Infernio/e0734de4373ec1cbdccc8827c2a91b21

This is on 4.1.3b. Same thing also happens when I just try to drag and drop the effects portion of one those records over into the partial override.
Can be tested with the ESM plugin from this mod: https://www.nexusmods.com/oblivion/mods/49096

Edit: And trying to add an EFIX subrecord takes xEdit down completely, no assertion failure or anything. Just closes instantly.

[Infernio]

Also, the decoding for OBME's SCIT/EFIX seems to be wrong? At least, according to OBME's documentation, the efixParam etc. is in SCIT, not in EFIX. As silly as that seems.

That, or OBME's docs are wrong 🤷‍♀️

[ElminsterAU]

OBME support is currently incomplete. OBME documentation is a mess.

[MacSplody]

Confirming that copy as override now works without issue in TES4Edit 4.0.3h (Hotfix 1).
Editing the copied record and saving changes also works fine.

@ElminsterAU Is there anything else I should test out for this issue?