3.0.1 Scan hangs after Google Safe Browsing

I can’t reproduce the issue.
What is your current configuration in the “Advanced Users Settings” section? You can show me a screenshot to make it simple, but make sure to hide your Google Safe Browsing key before uploading it.

WP: 5.5.3
PHP: 7.3
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Ninja Firewall

Firewall Enabled
Mode NinjaFirewall is running in Full WAF mode.
Edition WP Edition ~ Need more security? Explore our supercharged premium version: NinjaFirewall (WP+ Edition)
Version 4.2.6 ~ Security rules: 2020-10-29.1
PHP SAPI CGI-FCGI ~ 7.3.12

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Ninja Scanner

Advanced Users Settings

File integrity checker
x Always verify NinjaScanner’s files integrity before starting a scan.
x Compare WordPress core files to their original package.
x Compare plugin files to their original package.
x Compare theme files to their original package.

By default, only themes and plugins available in the www.remarpro.com repo can be checked that way. If you want to include premium plugins or themes too, consult our blog.

File snapshot x Report files that were changed, added or deleted since last scan.

Database snapshot x Report pages and posts that were changed, added or deleted in the database since last scan.

Anti-malware signatures x Linux Malware Detect + NinjaScanner

Google Safe Browsing Test API Key: Your API Key is valid

Files and folders x Do not follow symbolic links.
x Warn if symbolic links.

x Warn if hidden PHP scripts.
x Warn if unreadable files of folders.

Scanning process x Fork process using WordPress built-in Ajax Process Execution.
[NB using WP-CRON fails on initialising]

Scan report Display report: x On one page.
Row action links: x Show when hover on row.
Number of visible rows in table: 6 rows
File names: x Show absolute path.
x Highlight syntax when viewing a file.

Nerds Settings

File integrity checksum x Use SHA-1.

Debugging x Show the “Log” tab.
Sandbox x Enable the quarantine sandbox.

Run the garbage collector NEVER

I still cannot reproduce the issue with your config.
But the fact that you cannot start the scan using the “WP Cron” fork method likely means there’s a small problem somewhere.

1. If you disable the Google Safe Browsing scan (remove your API key), does it work?
2. If you open your browser’s console (CTRL + shift + j), do you see any error during the scan (using either the AJAX or WP-Cron method)?
3. Do you have any security plugin installed?
4. Were you able to run the scan using the “WP Cron” fork method with the previous version 2.x?
5. What error message does the “WP Cron” fork method return?