Firefox Community Forum

I'm reposting a question already opened here because a moderator suggested to do so. Actually I though I was posting to the international forum from the URL...

I was trying to access a local HTTPS website of an embedded device (a Siemens S7-1500 PLC) that is using a self-signed certificate, but was unable to go on (attached image #1, in Italian language) due to the the SEC_ERROR_REUSED_ISSUER_AND_SERIAL error. I've browsed a similar PLC webserver in the past, so the fact that the device exposes a similar certificate serial number is not so strange for me, considering also it's self-signed.

The problem is that I cannot follow the instructions of the Mozilla knowledgebase here because I'm not able to identify the correct certificate of the website!

In the attached image #2 you can see that the connection is detected as not encrypted, I suppose because only the form part of the HTML that is posting the data using HTTPS while the rest is using HTTP, but I'm not sure. If I click on the padlock icon (attached image #3) the info about the current certificate is not displayed.

Then I went into Tools > Options and searched for "certificates"; as you can see in the attached images #4 and #5, neither in the Servers tab nor in the Authorities tab I can find any item that is related to 192.168.10.2 (the webserver IP address) or Siemens (the embedded device manufacturer). But unfortunately the error persist! Initially there was a 192.168.10.2:443 line in the Servers tab and I removed it and restarted Firefox, but it didn't solve, so at the moment the situation is the one depicted by the attachments.

I had to use Microsoft Edge to access the website, but I would like to solve this issue and use Firefox instead. Is there anything else I can do to bypass the error? Why doesn't the error page provide a way to correctly identify the wrong certificate using its fingerprint and/or name? Or, maybe, is there a way to disable this check for local IP addresses or for items in a whitelist?

Thanks for your help.

Hi, I’m testing a WordPress website in Firefox and noticed that some recent changes (like text or small layout updates) don’t appear immediately. The site is using Cloudflare CDN and caching, and even after refreshing or clearing cache, the older version sometimes still shows.

 [[Website | https://restaurantstocustomer.com/]]

Could this be related to Firefox caching behavior? Is there anything specific I should check to make sure updates appear correctly?

Thanks in advance for any help.

I frequently need to access logs in HTML format from a particular application. I find Firefox more comfortable for this, so I visit the parent path directly in the browser. However, the default sort order is by name; since these are logs, it's more useful for me to list them by last modified time. Is it possible to make this sort order the default when visiting file:// paths?

I've attached an image of what I typically visit for completeness.

Thanks.

I've noticed for awhile that when exiting Firefox (currently 150.0.3) open tabs no longer close. When I re-enter Firefox (new start) I no longer get my home page. I've tried all key combination of exiting as well as the X. I searched this community and WWWeb and found nothing usefull.

Thank you for your attention to this matter. Rodney

when visiting websites using my vpn firefox blocks my entry. I have to disconnect my vpn to allow entry to sites. ive tries numerous fixes and nothing works its frustrating.

Hello! Please report this bug to the developers. When I first launch Firefox after turning on my computer, the window title bar and buttons in the upper right corner (like "Minimize," "Minimize to Window," and "Close") sometimes disappear. If I minimize the browser via the bottom taskbar and then restore it, these buttons and the title bar appear. I'm using Windows 10 x64, with a screen resolution of 2560x1440 (scaled to 125%, but I don't think this has anything to do with the scale or resolution, as other browsers (Opera, Edge) don't have these title bar issues).

See screenshots at the links: https://imgur.com/a/Hbc9yvE (There are two screenshots: 1 - with the window title and buttons (as it should be), 2 - when the window title and buttons disappear)

I've noticed that if I let Windows sit for a while after turning on the PC (2-3 minutes) and then launch Firefox, the problem with the disappearing title bar and buttons seems to disappear. Apparently, Firefox doesn't have time to load properly after Windows loads, and if I launch Firefox almost immediately after Windows loads, the problem described above occurs. And when the OS sits for 2-3 minutes, Firefox apparently loads all its services and processes normally and then works normally, without this error. Firefox ver.: 150.0.3.

This bug was also discussed on the forum by some other users, and they are also experiencing this bug: https://forum.mozilla-russia.org/viewtopic.php?pid=818805