If a user replies using the app does not see their answer or anybody else; other users using a browser see that reply as if it was "corrupted"; while teachers see all replies (independently of app/browser) correctly

This happens with old sites (3.7) as well as new ones (3.11)

To reproduce it:

1) [Browser1/teacher] Log in with a user with a teacher role, and create a new forum configured as  Q and A forum - OK

2) [Browser2/student] Log in with a user with a student role (u2), and double-check you cannot create questions - OK

3) [App/student] Log in with a user with a student role (u1), and double-check you cannot create questions - OK

4) [Browser1/teacher] Add a question - OK

5) [Browser2/student] Check that you can see the question - OK

6) [App/student] Check that you can see the question - OK

7) [Browser2/student] Reply to the question - OK

8) [App/student] Double-check that you cannot see any reply - OK

9) [App/student] Reply to the question - OK (at least apparently)

10) [Browser1/teacher] Double-check that you can see both replies - OK

11) [Browser2/student] You can see your own answer (u2) [OK], instead of seeing the other user's reply you can read [NOT OK]

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12) [App/student] You cannot see any reply (not even your own) - Not OK

13) [Browser1/teacher] Reply to both answers - OK

14) [Browser2/student] See that instead of the teacher's replies you can read [NOT OK]

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15) [Browser3/student] Log in with a user with a student role (u1), and double-check you can see your answer [OK], see that instead of the other user's answer and the teacher's replies you see [NOT OK]

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