Ubuntu: remove file generated by Firefox in the Home folder

Mozilla Firefox creates - and keeps on creating - an annoying "C:\nppdf32Log\debuglog.txt" file in your home folder, and keeping on deleting it is useless: every time you open Firefox, it's generated again.

A simple solution to this bug is to hide the file: in order to do that, create a new empty document in the same folder, and call it "hidden", without extension. Open it and copy the name (extension included) of the file (or files, and/or folders) you want to hide, then save and close. Rename the file by adding a "." at the beginning, so the final name should be ".hidden". Refresh the folder, or close and open it again, and the file will be hidden.

To see hidden files, or to see and edit the ".hidden" one, press CTRL+H on the folder, and again to re-hide everything.

Ubuntu - add a folder to bookmarks on the left panel

Bookmarking a folder on Ubuntu is easier as expected: just open the folder you want to have at hand in the left-hand-side panel, and from the above menu choose Bookmarks, and then Add Bookmark. In alternative, directly from the folder press CTRL+D, and a shortcut will be created in the bookmarks tab.

[SOLVED] Add custom characters to keyboard layout in Ubuntu

After a lot of attempts, which were not definitive, I finally managed to add some custom characters to my keyboard layout which were not included, avoiding to switch form one layout to another for just some characters.

Here I use as example how I added some German characters (ä,ö,ü,...) on my Italian layout.

• temporally change your layout with a similar one:
  Menu -> Keyboard Layout ->  Layout -> + -> chose a different one from your current (I chose English UK)
• open a terminal (CTRL+ALT+T)
• type cd /usr/share/X11/xkb/symbols/
• type ls to see all the layouts, and identify which one your was (in my case it, in the following steps substitute it with your layout)
• make a backup copy: sudo cp it it.backup
• open the file: sudo gedit it &
• identify the key you want to edit: if for example you want to add the "ä" as third option on the "A" key, search for the lines which contain "a" and "A" at the beginning; in this case it is:
      key <AC01> { [a, A, aring, Aring] };
• substitute the third element ("aring" or whatever you have) with "adiaeresis" and eventually the fourth with "Adiaeresis" in order to get an "Ä"; this in ALL lines (there can be more of them for different layout settings) where that specific key appears. 'A' key lines should then look like
      key <AC01> { [a, A, adiaeresis, Adiaeresis] };
• add other desired characters as well; if you don't know their code (e.g. "adiaeresis"), just look for them in that language's layout
• save & close
• in the Terminal type sudo dpkg-reconfigure keyboard-configuration and follow the on-screen instructions
• then type sudo dpkg-reconfigure console-setup and follow the on-screen instructions
• close all programs and reboot: sudo reboot
• after logging in go again to Menu -> Keyboard Layout ->  Layout, remove the previously set layout and add your default one; now, following the above example, you should be able to get an "ä" by AltGr+A and an "Ä" by SHIFT+AltGr+A