Firefox v71 and PDF Readers

I don't have your setup, but have you checked the Applications setting under about:preferences which sets how pdf files are treated? Otherwise, try using the internal pdf viewer - pdf file can be downloaded from it.

In Options (preferences) I have FF set up to use a PDF reader, the default PDF Reader/Editor.

Changing to FF's viewer makes things worse, in or out of the Sandbox the screen flashes, nothing happens.

I can set it to "Save file" but I want to be able to delete pages before saving. Prefer not to.

This is under "Applications" in FF.

The window that pops up that I referred is the Windows7 "Open With" window.

Same thing is happening with other apps.

System: Windows 10 1809 x64

Sandboxie: 5.31.4 & 5.31.6

Before updating Firefox to v71, the open-with pop-up in Firefox functioned properly (e.g., opening a rar\zip archive with winrar\7zip). At the time I was with Sandboxie 5.31.4.

After updating Firefox to v71, the open-with pop-up in Firefox no longer behaves as expected. This is, the save-as works OK, the the open-with no longer opens the desired app. Updated to Sandboxie 5.31.6, but the problem remains.

Running Firefox outside the sandbox works as expected without problems.

More details about the problem: Inside the sandbox, when choosing open-with, the associated app\program doesn't run, but Firefox shows the file as downloaded OK in the download tab (remember that I didn't choose to save the file, just to open it with some app).

In the about:downloads, the zip\rar\etc... file show as downloaded. Normally, if I double clicked on it, the associated app would open. Nothing happens when Firefox v71 is sandboxed.

However, If I right-click on it and choose "Open Containing Folder", sandboxie opens a Windows Explorer Window (sandboxed) in "<windows-drive>:\Users\<user-name>\AppData\Local\Temp" where resides the file I wanted to open through Firefox.

It seems that with the newer version of Firefox, whenever I run it sandboxed and choose to open some file instead of saving it, Firefox still manages to download the file to a temp folder, but is no longer able to open the associated app\program to show it.

Same thing is happening with other apps.

System: Windows 10 1809 x64

Sandboxie: 5.31.4 & 5.31.6

Before updating Firefox to v71, the open-with pop-up in Firefox functioned properly (e.g., opening a rar\zip archive with winrar\7zip). At the time I was with Sandboxie 5.31.4.

After updating Firefox to v71, the open-with pop-up in Firefox no longer behaves as expected. This is, the save-as works OK, the the open-with no longer opens the desired app. Updated to Sandboxie 5.31.6, but the problem remains.

Running Firefox outside the sandbox works as expected without problems.

More details about the problem: Inside the sandbox, when choosing open-with, the associated app\program doesn't run, but Firefox shows the file as downloaded OK in the download tab (remember that I didn't choose to save the file, just to open it with some app).

In the about:downloads, the zip\rar\etc... file show as downloaded. Normally, if I double clicked on it, the associated app would open. Nothing happens when Firefox v71 is sandboxed.

However, If I right-click on it and choose "Open Containing Folder", sandboxie opens a Windows Explorer Window (sandboxed) in "<windows-drive>:\Users\<user-name>\AppData\Local\Temp" where resides the file I wanted to open through Firefox.

It seems that with the newer version of Firefox, whenever I run it sandboxed and choose to open some file instead of saving it, Firefox still manages to download the file to a temp folder, but is no longer able to open the associated app\program to show it.

I can also confirm this problem with Firefox 71.0 and Sandboxie 5.31.6.

Same for me, very annoying.

Files with a linked application are stored in the AppData\Local\Temp\ directory, which is normal.

Files that are to be saved end up in the selected download directory.

Why the start does not work anymore, I don't know (yet). I wrote a question in the Firefox forum, maybe someone will help.