Several apps like the EaseUS MobiSaver can be used to extract the conversations out of Whatsap Sqlite message databases used on iOS devices. The conversions are saved as HTML files, each conversation in its own file.
Found 2 different conversion types using the same filename extensions.
Conversion sqlite to html type 1:
Convert from SQLite database to HyperText Markup Language web page.
Multiplatform software - convert sqlite to html on any platform
SQLite database manager
File type (from-> to)
Convert from sqlite file format
HyperText Markup Language web page
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned sqlite to html. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Conversion sqlite to html type 2:
Convert from WhatsApp Messenger for iPhone message database file to HyperText Markup Language web page.
Microsoft Windows software - convert sqlite to html on Windows
A recovery tool used to recover data from iPhone, iPod Touch and iPad
A database extractor for WhatsApp Messenger
Apple macOS / Mac OS X software - convert sqlite to html on OS X
iPhone, iPad and iPod Touch data recovery tool for Mac