Security Issue: Update your Flash Player Version 18.0.0.160
https://www.adobe.com/products/flashplayer/distribution3.html

See if there are updates for your graphics drivers https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

FredMcD said

Security Issue: Update your Flash Player Version 18.0.0.160
https://www.adobe.com/products/flashplayer/distribution3.html See if there are updates for your graphics drivers https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

No, it is not the problem of graphic card. The pages do not contains flash contents.

What I need is when there is "waiting for..." or "transing data from...", firefox always show page first, even if it is ugly and uncomplete.

Is this something you're noticing more with Firefox 39 than with earlier versions? Are there some sites that are particularly good (bad?) examples of this problem?

Coincidentally, I was looking at some Google webmaster help pages yesterday about how style sheets and scripts linked into a page will block rendering and how to minimize the wait time. Not helpful to you as the end user, I know, but perhaps if we compare one or two problem sites in Firefox and Chrome we can see a difference in how resources are loading or rendering.

If you are motivated to dig into this more, could you do this three-minute experiment:

Create a new Firefox profile

A new profile will have your system-installed plugins (e.g., Flash) and extensions (e.g., security suite toolbars), but no themes, other extensions, or other customizations. It also should have completely fresh settings databases and a fresh cache folder.

Exit Firefox completely and then start up in the Profile Manager using the Windows run dialog (or charms bar search box):

firefox.exe -P

Don't delete anything here!

Any time you want to switch profiles, exit Firefox and return to this dialog.

Click the Create Profile button, assign a name like TEST063015, and skip the option to relocate the profile folder. After creating the profile, select it and start Firefox in that profile.

Does Firefox render pages any differently, better or worse, in an uncustomized profile?

When returning to the Profile Manager, you might be tempted to use the Delete Profile button. But... it's a bit too easy to accidentally delete your "real" profile, so I recommend resisting the temptation. If you do want to clean up later, I suggest making a backup of all your profiles first in case something were to go wrong.

jscher2000 said

Is this something you're noticing more with Firefox 39 than with earlier versions? Are there some sites that are particularly good (bad?) examples of this problem? Coincidentally, I was looking at some Google webmaster help pages yesterday about how style sheets and scripts linked into a page will block rendering and how to minimize the wait time. Not helpful to you as the end user, I know, but perhaps if we compare one or two problem sites in Firefox and Chrome we can see a difference in how resources are loading or rendering.

---

If you are motivated to dig into this more, could you do this three-minute experiment:

Create a new Firefox profile

A new profile will have your system-installed plugins (e.g., Flash) and extensions (e.g., security suite toolbars), but no themes, other extensions, or other customizations. It also should have completely fresh settings databases and a fresh cache folder.

Exit Firefox completely and then start up in the Profile Manager using the Windows run dialog (or charms bar search box):

firefox.exe -P

Don't delete anything here!

Any time you want to switch profiles, exit Firefox and return to this dialog.

Click the Create Profile button, assign a name like TEST063015, and skip the option to relocate the profile folder. After creating the profile, select it and start Firefox in that profile.

Does Firefox render pages any differently, better or worse, in an uncustomized profile?

When returning to the Profile Manager, you might be tempted to use the Delete Profile button. But... it's a bit too easy to accidentally delete your "real" profile, so I recommend resisting the temptation. If you do want to clean up later, I suggest making a backup of all your profiles first in case something were to go wrong.

The best examples are:

Open any overseas page in China mainland.

China blocked any Google domain and make international access slow, so "waiting for..." always happen. The page still keep blank, even source of the page is downloaded.

It is not the problem in profile. For example, Tor Browser. When there is response, page keep blank until it is fully downloaded. It never show uncompleted page.

What I need is how to make firefox show uncompleted pages as soon as the server responsed the html source, never wait, even it is "waiting for" or "downloading data". (This will do great help for users in China.)

I don't know how similar or different the TOR browser is from regular Firefox.

If you know there are certain inaccessible servers, you may be able to use Adblock Plus or a site blocking extension to prevent Firefox from sending requests to them. You would need to build up your list of problem servers over time, but this might be the easiest workaround compared to actually changing how Firefox displays pages.

Firefox is going to wait for "blocking" resources, for example, a style sheet or script loaded in the head section of the page. If you want Firefox to render the HTML based solely on the initial file before retrieving and applying external files, I think you would need an add-on. I searched a bit but didn't see any references to such an add-on. Actually, I'm not quite sure how it would work.

An external filtering proxy (like the old Proxomitron program) could modify the page before it reaches Firefox, but creating intelligent rules is likely to be somewhat complicated and without extensive testing could wreck many sites.

Could you test shortening some timeout periods and see what effect that has? Here's how:

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the search box above the list, type or paste http*time and pause while the list is filtered

(3) You could experiment with these:

(A) network.http.response.timeout - I think "waiting" involves this setting - default is 5 minutes (300 seconds); try 20 seconds to see what effect that has. Note that some sites have long-running scripts which will fail with a change to this parameter.

(B) network.http.connection-timeout - I think "connecting" or "contacting" involves this setting - default is 90 seconds; try 20 seconds to see what effect that has.