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To ensure better compatibility, do a fresh save-as to another format if possible on MS side (docx-doc, doc-docx, -docm, whatever). It forces Office to rebuild the file, i believe, and usually it fixes some display mistakes coming from excessive formatting, trashes the leftovers of previous edits, etc, and the file itself becomes lighter. Some other tricks:

1. Have strict formatting rules and only select amount of styles. If you see them mutating, choose to select everything with a style-bastard applied, and then reapply their parent to all affected paragraphs (after what it should disappear);
2. Don't use rare fonts as long as possible, and if you do, on different machines too, copy them from Windows fonts folder in advance;
3. Overwhelmingly long and complex tables in Word usually break. The most dire offender is how you unite cells and move separate cells' borders, because it breaks their structure. Google has workarounds iand limitations on that in their products. To ensure your table translates right, copy it into Excel and then back after setting all cells in Excel to text data, as it likes to reformat e.g. 18.03.2025 into date format and such.

Some of these problems occured to me between different installations of MS products themselves, and with LO I had it the other way: Excel had a bugged file that wasn't adjustable in how to print it. One column wasn't fitting on the page one, but once I move the guideline over that column, Excel cuts this table into 70+ pages, one cell on each. The only thing that helped is opening this exact file in LO Calc where this problem just can't be reproduced. Since that I use Calc first, and then Google Sheets as I haven't found a fitting online sharing solution for myself and get invited tonedit it by others, and Excel is not an option at all anymore.

Same. I've had some professional frustrations when spreadsheets don't carry over formatting correctly and dealing with macros is a pain, but it's great to start with or if you aren't collaborating.