(Selenium Webdriver) Not able to click BROWSE button while uploading a file in GWT Framework

Hello all,
I am working with GWT application, Issue in clicking browse button : I have tried to click browse button it did not working , When I try to click browse it is click some-other  element  because the browse (Web-element)  blocked by other element when i try to spy that element it's working but it did not clicking the element :: 
Upload file in GWT frame work.

Note : The same work fine in CHROME, Facing issue with FIREFOX
Tried Steps:

1. Remove the blocking element using JS then try to click the browse button it's clicking but that function is not working.
2.Move the element then try to click button did not work.
3.
When I try to upload file using sendkeys it says """read only". "Desktop/package/file.txt"
4.So I remove that read only attribute using JS then try to send path location It just taking the whole path and says Upload failed.
5.In manually If i upload file works fine but it takes only the package not the path {"file.txt"} but the above method takes the whole I guess that is th problem If you have any idea Please let me know , Thanks in advance.



Thanks & Regards
Arun kumar.t