TWO CRITICAL BUGS: 1) File, "Save Page As" and 2) right-click the picture and select "Save Image As", both do not work at all in Firefox 27, 28, and 29!

Question

Note: capitals are used only to highlight important words.
PLEASE, TAKE THESE COMMENTS ON TWO CRITICAL BUGS VERY SERIOUSLY BECAUSE THE BUGS DESCRIBED BELOW ARE SO CRITICAL THAT I CANNOT USE THE LATEST VERSION OF FIREFOX UNLESS THEY DO NOT APPEAR IN THE LATEST VERSION AND THEREFORE I AM FORCED TO REVERT BACK TO FIREFOX 26.
I have Windows 7 64-bit and Firefox 26. I could not install Firefox 27, 28, and 29 due to the persistent presence of the two critical bugs described below. I have 8 GB of RAM and an Intel quad-core processor and a lot of hard disk space available.
I installed Firefox 27 and then Firefox 28 a while back and these two bugs described below were still present and now I have just checked again with Firefox 29 by installing it and yet again, these two bugs described below are present!! UNBELIEVABLE THAT THESE TWO CRITICAL BUGS ARE STILL PRESENT IN FIREFOX 29 WHEN I CLEARLY INFORMED YOU ABOUT THEM IN THE HELP, SUBMIT LINK OF FIREFOX!!
I am forced to revert to Firefox 26!
First, I use Windows 7 64-bit and I always use Firefox with at least 120 tabs opened. BUT I have 8 GB of RAM, an Intel core i7 quad-core processor and more than 1 TB of hard disk space. Consequently, I do not understand why I would have these two critical bugs.
With Firefox 26, I also have at least 120 tabs opened when I start Firefox and I do not have the two critical bugs described below, therefore I do not believe that the number of tabs is the reason of the two critical bugs that are present in Firefox 27, 28, and 29.
---FIRST CRITICAL BUG:
When I open ANY web page and do File, "Save Page As", the window that is supposed to open to locate the folder where I want to save this web page does NOT open at all, even if I wait a long time to see if it opens.
Same problem happened with Firefox 27, 28, and now 29!! When I reverted back to Firefox 26, this problem did NOT happen anymore!
---SECOND CRITICAL BUG:
When I use Google Images, for instance entering model in the search field of Google Images and then pressing enter.
Then I select any picture, open to a new tab this selected picture, then open a new tab by selecting the option View for this picture. Then right-click the picture and select "Save Image As".
Again, the window that is supposed to open to locate the folder where I want to save this picture does NOT open at all, even if I wait a long time to see if it opens.
Same problem happened with Firefox 27, 28, and now 29!! When I reverted back to Firefox 26, this problem did NOT happen anymore!
---THESE TWO CRITICAL BUGS DO NOT APPEAR WHEN I USE INTERNET EXPLORER 11.
I have no idea if you will be able to reproduce these two critical BUGS but I can assure you that they are not present when I use Firefox 26 and they are present when I use Firefox 27, 28, and 29. More, be aware that I have at least 100 tabs opened but I also have this same number of tabs opened in Firefox 26 and yet I do not experience these two critical bugs when I have Firefox 26!
Once again, these two bugs touch at two vital, critical very basic functions of Firefox and therefore I will NOT be able to use any version above 26 if these two bugs are still present, as they are present in Firefox 27, 28, and now 29!!!
Please, make it a priority to solve these two critical bugs. Thanks.
I did read a post related to the same issues “Firefox stops responding when trying to "save page" or "save image" | Firefox Support Forum | Mozilla Support” at https://support.mozilla.org/en-US/questions/991630?esab=a&as=aaq
I am still reading it again to try to figure out exactly what the person did to make his problems be solved, as the post is not clear at all on what solved the problems!
In any case, all the suggestions proposed in this post do not work and I surely cannot do a system restore when it is obvious that the two bugs do not appear in Internet Explorer.

Answer 1

First, I sent an email to the author of PhotoME to inform him of the serious issues his addon caused with Firefox latest versions.
Now, for those of you who do not have the PhotoME addon and yet experience the same problem that I had and that I described above, I suggest the following strategy.
As PhotoME did cause these problems with Firefox latest versions, I am pretty covinved other addons probably might cause these problems too. Therefore, adopt the following method.
Test one addon at a time to see if this particular addon is behind your Firefox issues like the ones I had.
So, disable one addon only at a time. Then close your Firefox and restart it from scratch and see if you still have your Firefox problems. You must restart the Firefox browser from scratch. If you still have these Firefox problems, re-enable the disabled addon, restart your Firefox (again!) and repeat the same method for every single addon that you have.
Try to be selective by choosing first addons that are more likely to cause your Firefox problems such as not very well-known or not very popular addons (like it was the case for the PhotoME addon).
If this method works or if it does not work, report it on this web page so that others can be helped with your comments.
I hope this method will help you because I was really upset that I had these Firefox problems and I first thought it was the fault of Firefox, only to discover later that this PhotoME addon was the culprit and had caused me such upset.