I was having the same issue. I am a website administrator and I was not able to download pdf documents that are in a pass worded section of the website. I was able to do this until I switched in January from an HTC Evo to the LG Optimus G. I just downloaded a different browser and I can access the documents I need. I also belong to a yahoo group and was able to send and reply to emails till recently. I just downloaded the Yahoo mail app rather than use the stock app in my phone and I'm able to send and reply once again. I guess the stock items that come with these phones aren't always the greatest. I'm so glad I found this article. 
