2051868 - macOS System Print Dialog bypasses "Open in Preview" and "Save as PDF" in Thunderbird v152 (macOS Tahoe / Apple M4)

Status: RESOLVED DUPLICATE of bug 2047850

(Thunderbird :: Untriaged, defect)

Description

[mdu22c]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/26.5 Safari/605.1.15

Steps to reproduce:

When I use the native macOS system print dialog within Thunderbird and select either "Open in Preview", Instead of opening the Preview app Thunderbird bypasses the command and immediately sends the document directly to the default physical printer. The same happens with "Save as PDF", the file-saving dialog is first presented, but after entering the filename the document is also sends to the default physical printer rather than being saved.

Environment:
OS: macOS Tahoe 15.5.1 (26.5.1)
Hardware: Apple M4 (Silicon)
Thunderbird Version: 152 (Issue present) / 151 (Works perfectly)

Actual results:

• Open an email in Thunderbird v152.
• Select Print...
• in the Print Dialog window, select "Print using the system dialog"
• The system print dialog is opened
• Click the PDF dropdown and select "Open in Preview" or "Save as PDF".

Result: The document is instantly printed on the physical printer instead of performing the macOS system action.

I have downgrade to Thunderbird 151, this works perfectly

Expected results:

The macOS action "open the Preview App" should have been triggered or the pdf should have been saved to the file system.