And users get upset if you force them to switch to LO, because it's not perfect at rendering Word documents (because MS doesn't want it to be).
That simply is not true: Microsoft opened up the file format many years ago. The problem with file fidelity is that to achieve identical rendering, you must FLAWLESSLY mimic every single behavior of the source program, including bugs.
You've been duped by OOXML, which was its main intention; to create a standard which so esoteric it's of little use to anyone else who wished to make a parity replacement for Word, yet ticked the government check boxes for open standards. ODT was standardised 2 years before OOXML, which MS pushed through in a hurry to in response to governmental push for open standards, they didn't want ODT to get a foothold. Note they chose not to act in good faith and use the ODT standards (meaningfully, or by default), or assist in their improvement. No, it was all about keeping the golden goose propped up.
Fidelity needs well documented on-disk standards AND rendering which adheres to those standards.
https://blog.documentfoundation.org/blog/2026/03/27/odf-is-the-future-ooxml-is-the-past/
Did you even read, let alone attempt to understand, my entire comment?!?
I haven’t been “duped”, I literally explained in detail why it’s impossible to have 100% document fidelity. Getting the data in and out — and whether it’s stored as binary or XML — is the easy part.
Knowing what to do with it is the hard part. As I said: you must flawlessly reproduce every single feature, behavior, quirk, and bug.
The only point you and I differ in is whether this fact is deliberate or not: you claim it is. I maintain that it doesn’t matter whether it is deliberate or not, because from a technical standpoint, it’s an impossible task regardless. Microsoft didn’t have to try and be evil: technology made it impossible anyway.
Those governments which wanted Office to switch to “open” file formats did not understand that what they were asking for is not actually possible. So it’s no wonder they got a kludge that technically checks the box, but doesn’t really do what they wanted. That kinda tends to result from unrealistic expectations.
Microsoft fully documented both the binary and XML formats, but having the documentation still leaves you with the monumental/impossible task of recreating the Word engine to actually make full use of the data. OOXML simply changes the container format for the data. It doesn’t change the document object model, which is inherent to the way Word works. You
can’t use any other document object model without translation, which is going to be lossy in at least
some situations.
Those are your only two options: translate the data or recreate the entire rendering engine.
And the reverse is equally true: since Word can’t change its engine, for it to work with ODT, it must use a translator, which it does. But translation is lossy. (And honestly, Word’s ODT support isn’t that bad.)
My main point, though, is simply this: don’t act like the task at hand was trivial, and the only reason it doesn’t work perfectly is because MS sabotaged it. In reality, while I’m sure MS didn’t really want to do it, the sheer difficulty of the task makes perfection impossible, even if you want to do it.
As others have pointed out: even between different versions of Word, there can be fidelity issues. And that’s something MS
definitely didn’t do on purpose.