How to screenshot a file on your computer
If a web address starts with file://, the browser needs permission to read it. You only need to turn it on once.
one switch, one reload1. Open extension settings
Open your file in the browser.
Click the Snapify icon, then click the black 'Open extension settings' button.
2. Turn on Allow access to file URLs
On the settings page, look for the last row.
Click the switch to turn it blue. You can leave the other switches alone.
3. Reload the file tab
Go back to the tab with your file.
Open Snapify again and click the Reload Page button in the yellow bar.
4. Take the screenshot
Snapify is ready to use.
It works exactly like it does on normal websites.
If it still does not work
Check that the address starts with file://
Check that the switch is blue on the extension settings page
Make sure you reloaded the tab with the file, not the settings page
On Firefox, go to about:addons, click Snapify, look for Allow access to file URLs and turn it on. Then reload your file tab once.
Questions
Why can't Snapify screenshot a file by default?
Browsers block extensions from reading files on your hard drive for security. You have to give explicit permission.
Where is the switch?
It is in the browser's own extension settings page, not inside Snapify's UI.
I turned it on but it still asks for permission.
You must reload the tab with your file after flipping the switch. The browser does not apply the new permission until the page reloads.
Do I have to do this for every file?
No. You only do it once. It applies to all files.