LastModifiedInfo
Notify Last Modified Date & time of web page .
Get the date from http protocol sended by web server.
Sometimes server or browser set current time, so in that case , lastModified date is unreliable to check update the page.
LastModifiedInfo - Web Page Last Modified Date & Time Firefox Add-on
LastModifiedInfo is a Firefox add-on that notifies the last modified date and time of web pages. It retrieves the date from the HTTP protocol sent by the web server, ensuring reliable update information even when the server or browser sets the current time.
Add-on stats
Weekly download count: NaN
Firefox on Android: Yes
Risk impact: Very low risk impact 
Risk likelihood:
Manifest version: 2
Permissions:
- activeTab
- storage
Size: 26.49K
Ranking
Other platforms
Not available on Chrome
Not available on Android
Not available on Edge
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Add-on summary
Icons made by Freepik from www.flaticon.com is licensed by CC 3.0 BY
You can choose two notify type. one is javascript alert , another is html popup . html popup design is customizable, and html popup fade automatically(Don't need click :p ).
FAQ ・Don't show popup html msg. It might be that popup msg is hidden by page container. so rewrite z-index value more depth (like 1000 ->99999) in css. (open this addon option page, then rewrite css property in textarea property of popup)
User reviews
Sadly naturallucky seems to have last updated his Add-Ons in 2018. It is really a shame because his Add-Ons seem to be really great.
by Firefox user 17628373, 2023-04-15
Add-on safety
Risk impact
LastModifiedInfo does not require any sensitive permissions.
Risk likelihood
LastModifiedInfo is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.
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