1658289 - Thunderbird changes to be compatible with the Firefox printing changes for Fission

Status: RESOLVED WORKSFORME

(Thunderbird :: Upstream Synchronization, task, P1)

Description

[Jonathan Watt [:jwatt]]

There are various changes that need to be made to how printing works to make it compatible with the Fission project. I'm not exactly clear on the impact on Thunderbird but I'm filing this bug to try and provide some advanced notice.

One change that is going to be made is that the platform code will no longer be able to open the print dialog on behalf of the app. The app will be required to open the printing dialog, collect the users choices into an nsIPrintSettings, and only then invoke the platform printing code, passing that print settings object (and for now, during the transition period, setting printSilently on that object).

Another change that we'll be making for Firefox is that the frontend code will always need to create a browser element into which the document to be printed will be cloned (so a hidden tab in the case of silent printing). Cloning is required for Firefox in order to have a static snapshot of the document to be printed that doesn't change while printing is ongoing. It's possible that if Thunderbird can guanantee that the original document doesn't mutate and won't unload, that we could potentially have a mechanism to allow printing directly from the original document. I don't think that would add much complexity, but it may do, and in any event it may just be better for Thunderbird to follow the same structure as Firefox to avoid problems.

Wayne, I'm not sure who should be notified of this bug on the Thunderbird side. Maybe you could make sure the relevant people are notified?

Comment 1

[Wayne Mery (:wsmwk)]

Will need lots of testing of course.

NI Magnus to organize architecting.

Comment 2

[Magnus Melin [:mkmelin]]

Is there some meta-bug tracking the Firefox work (except bug 133787)?
When do you expect to do the changes? It would be useful to link in the corresponding Firefox bugs here.

Comment 3

[Jonathan Watt [:jwatt]]

The meta bug and its tree of blockers is:

https://bugzilla.mozilla.org/showdependencytree.cgi?id=1557645&hide_resolved=1

I'm not sure exactly how the work will be split yet, but it will probably land in v82 given there's a requirement to get Fission printing working in that timescale.

Comment 4

[Wayne Mery (:wsmwk)]

none of this will eventually be pushed in to esr78, correct?

Comment 5

[Jonathan Watt [:jwatt]]

Correct, this will not be backported to esr78.

Comment 6

[Magnus Melin [:mkmelin]]

I think the Firefox work on this basically completed, so let's close this.