Problems receiving long text-only MMS messages - org-xmlpull error

[pi99y]

Checklist

• [X] I can reproduce the bug with the latest version given here.
• [X] I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• [X] I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• [X] I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
• [X] I have taken the time to fill in all the required details. I understand that the bug report will be dismissed otherwise.
• [X] This issue contains only one bug.
• [X] I have read and understood the contribution guidelines.

Affected app version

1.0.0

Affected Android/Custom ROM version

LineageOS 20

Affected device model

Xiaomi Poco F1, Motorola Moto g100

How did you install the app?

F-Droid / IzzyOnDroid

Steps to reproduce the bug

Problem occurs when you receive a (long) text-only MMS from a sender using a different messaging app.

Example: Using Google Messages (updated Jan 18, 2024) send a long text message which gets converted to MMS due to it's length. I first found out about this when I got a MMS from a stranger (so don't know the app they were using) and then asked a friend to test with me with their Google Messages app. Since we immediately recreated the problem I doubt Google's app is the only one causing the problem.

Problem only happens with text MMSs and not long SMSs. Since Goog's app was unable to produce a short text-only MMS only long text was tested. We tested MMS picture + text which did not trigger the error. Admittedly the text there was short. Unfortunately I cannot re-test.

If using Fossify-Messages to SEND with "combine long texts to MMS" the problem seems not to be there - but this may be due to reverse role (sender vs receiver).

Expected behavior

Application should be able to display such messages even if the sender's app uses different ~formating.

Actual behavior

When the problem occurs the received message may appear empty / or be displayed but it will always produce a org-xmlpull error message (see screenshots)

Screenshots/Screen recordings

Error in Fossify Messages:

QKSMS:

LineageOS's Messaging:

Additional information

One thing I noticed when re-opening these tests in other messaging apps (see attached images) -QKSMS and LineageOS's default "Messaging" is that the problematic MMS had a subject line displayed there "subject: MMS". Long text MMS produced Fossyfy did not have the subject. The sender did not write the subject their app produced it without their knowledge. Fossify does not show those subject lines.

It appears it's either the length of the text in MMSs or inclusion of the subject that produces the error. It also happens with only ascii characters as well if you're wondering.