555745 - "Save Page As" etc. should warn re: plugin content

Status: UNCONFIRMED

(Toolkit :: Downloads API, enhancement)

Description

[J. Kanowitz]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.8) Gecko/20100214 Ubuntu/9.10 (karmic) Firefox/3.5.8
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.8) Gecko/20100214 Ubuntu/9.10 (karmic) Firefox/3.5.8

'Never underestimate human stupidity.'  A pet user used once again used File -> Save Page As for a number of important [filled] PDFs, and naturally wound up with a number of blank ones on disk.

While my particular user accidentally used the MAF extension - https://www.mozdev.org/bugs/show_bug.cgi?id=22671 - I notice "Portable Document Format" is now an option as of Firefox 3.5.x and 'fails' equally, and maybe more egregiously - seeing the PDF format recognized sends an even stronger false signal that filled fields might be saved, when of course the browser doesn't even know about them and the plugin's own 'Save' method must be used.

Anyone with a clue about plugins understands this, but normal humans don't understand plugins, and some are exceptionally resistant to absorbing the explanation.

Reproducible: Always

Steps to Reproduce:
1.  Permit a "normal human" access to the tubes, which contain PDFs with fillable fields.
2.  Let them spend hours filling a PDF.
3.  Let them attempt to save their work unsupervised.
Actual Results:  
User uses File -> Save Page As, does not look at filename or extension, remembers to navigate to destination directory on a good day, clicks Save blindly, sees nothing to suggest it did not work.  Fails to appreciate error until asking "IT" how to retrieve their unsaved work a month later.

Expected Results:  
User forced to think when a dialog pops up, or large red blinking text appears in the 'Save Page As' dialog.  

Suggested text along the lines of:
"WARNING:  This page contains plugin content [application/pdf].  Clicking 'Save' will save the file as I loaded it.  If you have made changes to the plugin content, you must use the plugin's Save method to save your work."

Many users don't read 'scary' warnings, but that's no reason not to serve the ones that would if they existed.  Cramming the warning into the "Save Page As" filepicker would avoid the annoyance of a modal dialog at the expense of the additional screen space used.