Are any gadgets involved / Does that also happen with safemode? See https://www.mediawiki.org/wiki/Help:Locating_broken_scripts

Loading VE on desktop via the section edit button is no different than loading it via the regular edit button, we just scroll you to the section you clicked on, so that is unlikely to be the cause.

Could be a Parsoid bug too.

Hmm ... very strange ..., I tried to replicate a number of ways and I couldn't replicate it (whether with Edit button or Edit Section button). The discussions (read via Google Translate) also refer to summary referring to the wrong section which is also weird. That may be a useful clue to pursue. Wonder if this bug is specific to nlwiki or if it is impacting other wikis. And, looks like only a handful of users seem to be running into this (is it because they are the ones who use Edit Section links more than others OR if there is something about their editing environment that is triggering this bug).

For the record: I asked the users involved to try the suggestion by aklapper and report back.

@Effeietsanders, do you have https://nl.wikipedia.org/wiki/Gebruiker:BarkingFish/GoogleTrans enabled in https://nl.wikipedia.org/wiki/Speciaal:Voorkeuren#mw-prefsection-gadgets ? That gadget has been associated with some weird problems in the past.

@Whatamidoing-WMF (un)fortunately, I'm not one of the people affected by this bug. I'll ask though!

Thanks for asking. I see that Thieu isn't using the GoogleTrans gadget, so that's not the source of the problem.

The diffs look like the content of the whole page (including the user's edit to one section) was saved as the content of just that one section, instead of the whole page.

VisualEditor has two modes for section editing – one that edits the whole page and just scrolls to the section, and another that actually edits only one section. We use the first on desktop and the second on mobile. Possibly it can get confused about which mode it is in – maybe when restoring from autosave, or switching between the mobile and desktop site?

More people have been reporting this recently again in https://nl.wikipedia.org/wiki/Wikipedia:De_kroeg#Bonje_met_de_visuele_editor:_artikeltekst_verschijnt_twee_keer_tijdens_bewerken

Hi,

At first, the issue seemed to happen completely random, but today I did a couple of tests and I was able to reproduce it twice:

• https://nl.wikipedia.org/w/index.php?title=ITIL_4&diff=prev&oldid=64517263
• https://nl.wikipedia.org/w/index.php?title=Scouting_in_Nederland&diff=prev&oldid=64517238

REPRODUCTION WHILE LOGGED IN AS "Sietske"

1. Access an article with multiple level 2 sections (==)
2. Press on "bewerken" (edit) next to a level 2 section (==)

Expected result: I am able to edit the section (and only this section) in the visual editor mode
Actual result: I am able to edit the entire page ==> DON'T THINK THIS IS OK???

3. Edit the level 2 section
4. Save the page
5. Check the page

Expected result: only the changes I made in step 3 are updated
Actual result: only the changes I made in step 3 are updated ==> OK

6. Press on "bewerken" (edit) next to a level 2 section (==)
7. Edit another level 2 section than the one you are supposed to edit
8. Save the page
9. Check the page

Expected result: only the changes I made in step 3 are updated
Actual result: the changes I made in step 3 are updated, and all other sections appear twice in the article ==> NOT OK

REPRODUCTION WHILE LOGGED IN WITH A NEWLY CREATED ACCOUNT
0) Create a new, clean account.

I've created a new account called "Sietske T312736"

1. Access an article with multiple level 2 sections (==)
2. Press on "bewerken" (edit) next to a level 2 section (==)

Expected result: I am able to edit the section (and only this section) in the visual editor mode
Actual result: I am able to edit the entire page ==> DON'T THINK THIS IS OK???

3. Edit the level 2 section
4. Save the page
5. Check the page

Expected result: only the changes I made in step 3 are updated
Actual result: only the changes I made in step 3 are updated ==> OK

6. Press on "bewerken" (edit) next to a level 2 section (==)
7. Edit another level 2 section than the one you are supposed to edit
8. Save the page
9. Check the page

Expected result: only the changes I made in step 3 are updated
Actual result: only the changes I made in step 3 are updated ==> OK

RESULT
The issue occurs for user "Sietske", but it does not occur for user "Sietske T312736"

CONCLUSION
It seems that the issue is a result of "something" in my user profile that is different from a default user profile.

I've just tested on the Spanish wikipedia: https://es.wikipedia.org/w/index.php?title=Tlapa_de_Comonfort&diff=151930281&oldid=150554170
I could not reproduce the issue there.

@Sietske Thanks a lot. I believe the ability to edit the entire page is by design (although it is a bit confusing, i agree). I was unable to reproduce it myself so far this way, but trying to turn on some features to see if I can find it too.

@ssastry @Whatamidoing-WMF we now have a volunteer who's able to reproduce the error. Please let them know any additional questions you may have to drill down to the cause :)