When I try to start chrome I get a message that says "Failed to load extension from: .Manifest file is missing or unreadable"

After finally fixed it by deleting all the .desktop entries for chrome.

find ~ -name "*chrome*.desktop"
#and then after looking at the list and maybe looking inside the files and deciding
#that you are ok with deleting them just to see if this fixes it....
find ~ -name "*chrome*.desktop" | xargs rm
#or something like
find ~ -name "*chrome*.desktop" | xargs gvfs-trash
#or maybe just save them in a folder or rename them while you make sure
#this is the problem

I can't reproduce the situation so I can't tell you for sure if this was it, but it might be worth a shot if you have the same problem.

I ran into this problem as a result of an incompletely installed extension. The extension, chromium-lwn4chrome, was installed through aptitude. I've got no idea how some of its files ended up not being installed.

I finally found it by running

strace -ochromium.strace chromium

In the chromium.strace file, I searched for the string "anifest" and found the lines

 lstat("/usr/share/chromium/extensions/lwn4chrome", 0x7ffd0c3bc520) = -1 ENOENT (No such file or directory)
 access("manifest.json", F_OK) = -1 ENOENT (No such file or directory)

Searching for lwn4chrome, I found

 open("/etc/chromium.d/lwn4chrome", O_RDONLY) = 3

Investigating that file, I found

export CHROMIUM_FLAGS="$CHROMIUM_FLAGS --load-extension=/usr/share/chromium/extensions/lwn4chrome"

but there was no file or directory named /usr/share/chromium/extensions/lwn4chrome on my system. I purged the chromium-lwn4chrome package, and the problem went away. I then reinstalled it (because I was curious) and this time everything worked.

Had the same problem. This is how I fixed it:

apt-get remove google-chrome-stable
export CHROME_VERSION="google-chrome-stable"
wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | apt-key add - 
echo "deb http://dl.google.com/linux/chrome/deb/ stable main" >> /etc/apt/sources.list.d/google-chrome.list
apt-get update -qqy
apt-get -qqy install ${CHROME_VERSION:-google-chrome-stable}
rm /etc/apt/sources.list.d/google-chrome.list
rm -rf /var/lib/apt/lists/* /var/cache/apt/*

I solved it opening chrome and navigating to chrome://version/

It showed me the following:

Chromium: 71.0.3578.98 (Versão oficial) snap 64 bits
Revisão: 15234034d19b85dcd9a03b164ae89d04145d8368-refs/branch-heads/3578@{#897}
SO: Linux
JavaScript: V8 7.1.302.31
Flash: (Desativada)
Agente do usuário: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) snap Chromium/71.0.3578.98 Chrome/71.0.3578.98 Safari/537.36
Linha de comando: /snap/chromium/562/usr/lib/chromium-browser/chrome --no-default-browser-check --no-first-run --password-store=basic --ppapi-flash-path --flag-switches-begin --flag-switches-end
Caminho do executável: /snap/chromium/562/usr/lib/chromium-browser/chrome
Caminho de perfil: /home/wagner/snap/chromium/562/.config/chromium/Default

the last line above is my PROFILE PATH

Pay attention on the last line which you need to point to your profile path. You need to set the ExperimentalOption to false as well. I set my ChromeOptions like this:

ChromeOptions options = new ChromeOptions();
options.addArguments("disable-infobars");
options.setExperimentalOption("useAutomationExtension", false);
options.addArguments("user-data-dir=/home/wagner/snap/chromium/562/.config/
chromium/Default");

driver = new ChromeDriver(options);

Enjoy!