What steps will reproduce the problem?
1. Open EbookDroid
2. Go to library
3. Click on a pdf file 

What is the expected output?
The pdf file should open


What do you see instead?

A message saying: 'Opening this document requires installation of the separate 
decoder plugin. Our application can provide the following one. Please confirm 
installation and usage:
This standalone PDF and XPS decoder with command line interface is based on the 
MuPDF library released under GPL licence.
According to the GPL, SOURCE CODE can be downloaded from Google Drive.'


What version of the product are you using?
v2.2.4

On what operating system?
Android 4.4.2


What device are you using?
THL 5000


Please provide any additional information below.

This is very strange. Until today I had no problem reading pdf files. Even 
today I opened one successfully. However, just a couple of hours after that I 
tried to open the same pdf file and it produced the message above. I the 
meantime I haven't made any updates to my system or to the software. Actually, 
I haven't switch on the internet at all. How come that EBookDroid suddenly 
stopped opening pdf files?