Hi aprilde33, it's possible these are related to some downloads, but that's just a wild guess. Can you open one or a few of the files in TextEdit and see what is inside? For example, it could be web page code, or just a message, or some encoded stuff that was meant to have a different file extension (such as .pdf).

The as.php file that opens without a prompt only occurs when using Firefox; does not occur using Safari. Am using a MacBook Air with latest Mojave OS.

Hi boodent, when you say the as.php file opens without a prompt, do you mean it opens in a Firefox tab? Or does it trigger a download dialog? Is there any pattern to it, for example, it occurs more with certain websites?

It happens with different web sites, but only when using Firefox. A box opens for me to type in. I close the box and it will reappear again. I close again, and it usually does not reopen. The as.php will sometimes open with Text Edit, other times no identifiable app. Again, this does not happen using Safari. Ted

Hi Ted, what do you mean by this --

A box opens for me to type in.

Is that a web form, or a download/save file box, or what? Can you share a screenshot of it?

I believe it is a download/save file box that allows one to type in info. Sometime, the tab for Text Edit replaces the Firefox tab in the upper left of the top info bar. Thanks for your response. Ted

Hi Ted, if this happens pretty frequently and reliably on certain sites, could you test in Firefox's Safe Mode? In its Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, any userChrome.css/userContent.css files, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the option/alt key when starting Firefox. (On Windows, hold down the Shift key instead of the option/alt key.)

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" Help button > Restart with Add-ons Disabled
• (menu bar) Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any difference?

Many thanks. I will try your suggestions. Ted

This has been happening to me today as well. It seems to open this message only when I have Yahoo Mail open.

This only happens in Firefox and not on Safari.

Hi kathrynnt, could you share the URL of the download? If you save one of the files, then you can use the Downloads list on the toolbar. Right-click (with one mouse, Ctrl+click) the download and click Copy Download Link. Then you can paste that into a reply here.

Hi Folks, Several weeks ago I had the same problem as kathrynnt regarding as.php file frequently opening up on my screen [MacBook Air] when reading an article using Firefox as my browser; this did not happen using Safari. After trying various recommended fixes, which did not fix this issue, I gave up. Then, I suddenly realized one day that I was not having the as.php problem. It has now been one month since the problem went away. My conclusion: Something was going on with Firefox that caused this problem and it has been fixed by Mozilla. Time will tell. Ted

@jscher2000. the downloaded files are empty. There are no url or the download that I could find. The files are zero bytes Plain Text but a ton of them. attached a screenshot of the current downloads after I selected the TextEdit option.

Originally, the messages came up as:

You have chosen to open: as.php which is Plain Text Document (0 bytes) from https://ads-us.rd.linksysnergy.com

What should Firefox do with this file? -Open with TextEdit (default) -Save File

Hi kathrynnt, that looks like an ad server related to "affiliate" links.

I would think an ad server would like to fly under the radar, and sending empty files as downloads is not what they intended. Is it possible that one of your ad blockers, either a Firefox add-on or an external security filter, is somehow converting these requests to empty files??

Alternately, is it possible that you have a rogue extension generating revenue for someone by clicking links? You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

• Command+Shift+a (Windows: Ctrl+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then cast a critical eye over the list on the right side. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage.

Anything suspicious or that you just do not remember installing or why? If in doubt, disable (or remove).

Any improvement?

Thank you jscher2000! After opening the Firefox add-ons, the problem seemed to have resolved itself.

same exact problem - mojave, firefox only. as.php opens as blank text. no add-ons at all. I refreshed Firefox, no solution. I think safe mode also had this problem (helping someone else who is not computer-proficient). I will reinstall firefox when i have the chance.

Hi reredouble, can you identify any filtering software on the Mac that might modify ad server responses? For example, many security suites filter web browser sessions and might have ad filtering features.

Since that looks like an unimportant site, if you are helping someone trying to solve the problem, you might consider trying to block ads-us.rd.linksynergy.com using the hosts file.

Corrected typo in the domain

Thank you for your help in surfacing this issue.

I raised this with the Firefox team via Bugzilla to see if they can resolve it. I appreciate all your work to help identify this issue.

See also:

• bug 1582848 - download pop-ups for as.php opened from yahoo.com pages for some users
• bug 1583366 - Add an intervention for yahoo mail