Blank "new notification" mail

Describe the issue or problem
Hi,
New issue published a couple of days ago resulted in a blank new notification mail sent to all users. Only journal initials in subject and journal signature at mail footer content where sent.
The last issue being published prior to that (oct 2022) was notified correctly.
We use Spanish as primary locale, and English and Portugues (Brasil) as additional languages

Steps I took leading up to the issue

  1. Had a look to email templates
  2. Located “New notification from” template
  3. Found that Portugues (Brasil) language template was empty. But globe icon green.
  4. Filled in Portugues (Brasil) with text
  5. Did not try to “Reset” as had no button to do so
  6. After adding Portugues (Brasil) text for template, globe icon went lilac colour, and then had “Reset” button displayed

I don’t know if the absence of a language in mail templates may result in mails being sent blank in all languages. Can’t quite understand why the globe icon was green despite a language was missing (or not displayed). Also don’t understand why globe icon goes lilac when all three languages are completed.
All mails templates have Spanish and English text. Some 50% of templates have Portuges (Brasil) blank (with green globe icon)

Might any data cache clearance have affeceted?

What application are you using?
OJS 3.3.0.10
single-journal
upgrade history: 2.4.8.0, 3.0.2.0, 3.1.1.4, 3.2.1.1, 3.3.0.10

Additional information
Sample mail template with blank text for Portugues (Brasil) and green globe icon

Sample fully translated template with lilac globe icon

Will appreciate any help.

Thanks in advance.
Regards,
Juan