I have a fix for this bug on the Lubuntu, which I hope will also work on Ubuntu. Should I post here or create a new thread? BTW this is not a bug in Windows.
Edit the file codeblocks-17.12/src/plugins/codecompletion/codecompletion.cpp
Goto line 680 and change Ctrl-Shift-. to something else (e.g., Alt-Ctrl-Shift-.) because it's a key duplicate to "Goto declaration" I set it to Ctrl-. and then changed "Goto implementation" to F8.
For some reason on my OS, Lubuntu 18.10, nothing works that's assigned to Ctrl-Shift-. Perhaps OS related? I disabled all of the shortcut keys in Lubuntu that I'm aware of by going into Preferences -> LXQt settings -> Shortcut keys. So on line 677 change from Ctrl-Shift-. to something else. I changed it a single key press F7 because I use it a lot.
On line 678 I change Ctrl-. to F8 but you can change it to whatever you like or leave it as Ctrl-.
Next you need recompile the source code:
While in the directory codeblocks-17.12 type make
Then type sudo make install
For anyone who would like to compile the source code, here's everything I did. Please note there might be a few lines that do nothing. Sorry I haven't taken the time to strip out the lines that do nothing. I was just in hurry to install the required libraries and stuff, so I think there are a few times I typed the wrong name, but it's not a problem. Apt-get install will simply tell you there's no such thing. If you find out which steps do nothing, then please let me know.
How to make/compile CodeBlocks IDE 17.12:
Download codeblocks_17.12.tar.xz into your Downloads directory.
Type the following lines
tar xvf codeblocks_17.12.tar.xz codeblocks-17.12/
cd codeblocks-17.12/
sudo apt install autoconf
sudo apt-get install build-essential libtool
sudo apt-get install libwxgtk2.8-dev wx-common libgtk2.0-dev
sudo apt-get install apt.cache
sudo apt-get install wx2.8-headers libwxgtk2.8-0 libwxgtk2.8-dev
sudo apt-get install wxWidgets
sudo apt-get install libwxgtk2.8-dev
sudo apt install libwxbase3.0-dev
sudo apt install libwxgtk3.0-dev
sudo apt install libwxgtk3.0-gtk3-dev
wx-config --version
cd Downloads/codeblocks-17.12/
sudo apt-get install gtk2.0
autoreconf -fi
./configure
make
sudo make install
sudo ldconfig
To start codeblocks and have the ability to set breakpoints and debug I created a file called cb in my home directory ~. Here’s how to create the file in your home direction.
cd ~
nano cb
While inside the file cb type:
codeblocks admin:///root/
Make cb an executable:
chmod +x cb
Type the following in your home directory to start codeblocks:
./cb
I hope this helps someone.