Update v5.5.102 breaks emails' HTML

Hello everyone,

after updating to v5.5.102 my emails (which previously displayed just fine) show up as empty. Checking the source code reveals that the HTML appears to be “scrambled” compared to earlier emails which contained regular HTML. The PDF file attached can be extracted and seems to be working though it also does not show up in every mail client, for example in Mail on iOS is does not show it.

I’ll include an incomplete snippet of how the email’s source code looks:

    <div class=3D"co
        <div class=3D"body_wrapper">
            <div class=
                <img class=3D"logo" src=3D"https://redacted.tld
/rechnung/logo.svg" />
                <h3 class=3D"heading"=
>Neue Rechnung</h3>
Sie erhalten mit dieser E-Ma=
il die Rechnung <b>1128-23</b> vom 3. April 2023 =C3=BCber <b>11,90 =
=E2=82=AC</b> im Anhang.
Alternativ k=C3=B6nnen Sie die Rechnu=
ng auch online einsehen und dort herunterladen:

I checked the change log of v.5.5.102 and saw that there were changes to email handling. Is this an issue with my templates, i. e. something I am doing wrong or is there a bigger issue with Invoice Ninja breaking encoding here at play?

Any help would be greatly appreciated.


@david any thoughts?

It looks like sometihng is escaping in your template. Is this a custom design?

@david I’m using a custom design. I checked the HTML and could not find anything suspicious. I also did not change anything from last week when it last worked.

I’ve checked again and I simply cannot understand what goes wrong. The email gets displayed correctly in the left preview pane when sending it. It shows up blank, I’ve checked with several email clients and my customers also face the same issue. The W3C’s HTML validator finds no issue with the HTML. When I switch from custom template to the “Simple” template the email shows up with content.

Any new ideas?