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Flash keeps crashing and freezing FFox 18


a crash per hour or so:


Chosen solution

If you aren't already using it try the Memory Fox add-on. That made a big difference for me. Also try UnloadTab which unloads (but not closes) any tab that hasn't been selected in some specifiable amount of time. Like 10 minutes. Selecting a tab that has been unloaded takes just a bit longer than a loaded tab but it's not particularly noticable.

I seem to remember reading somewhere that a recent release included the equivalent of UnloadTab but I am not sure of that.

I'm on 19.0 now and with 5 windows and 152 tabs FF rocks for me.

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Additional System Details

Installed Plug-ins

  • Shockwave Flash 11.5 r502
  • 5.1.10411.0
  • np-mswmp


  • User Agent: Mozilla/5.0 (Windows NT 6.1; rv:18.0) Gecko/20100101 Firefox/18.0

More Information

DonGateley 1 solutions 28 answers

You are very welcome. I well know how frustrating this can be.

Once again, though, I urge you to upgrade Flash and keep it that way. These new vulnerabilities cannot be taken seriously enough. The browser Java exploit that appeared in mid January and attacked me (which was the nail in the coffin among all vendors for browser Java) took me weeks to recover from during which time I had to unplug from the internet completely. It emptied my Windows FIrewall which opened the door to any old mischief and then froze it so that it could not be fixed or modified in any way. Finding a cure for that and a way to restore it had me nearly crazy and I'm still in fear of a latent, or not so latent, time bomb. I learned a whole lot along the way but I sure don't recommend it if you need to get anything done.  :-)

glynh 0 solutions 3 answers

I changed to Water Fox and have had no problems since.

Question owner

Hello again, Heres an UPDATE:

- If i use:

FFOX 19 + UNLOAD TAB + FLASH 10.3 = pro: no problems, no crashes, no slowdowns cons: vulnerability.

FFOX 19 + UNLOAD TAB + Memory fox + FLASH 11.5 = problems started again, less slowdowns but crashes once an hour.

So, is a flash problem for me, i know using Flash 10.3 is a risk but seems to be the only option for a smooth and free of crashes journey... i still havent tried waterfox.

Thx friends.

  • Top 25 Contributor
  • Moderator
251 solutions 3015 answers

If you don't have memory fox with flash 11.5, does it make a difference?

Question owner

If I use MemoryFox the slowdown is less

but doesnt goes so smooth and fast as with flash 10

also, it crashes much less than before, but still crashes from nowere.

(FFOX 19 + UNLOAD TAB + Memory fox + FLASH 11.5)

Question owner


FFOX 19.0.2 + FLASH 11.6.602 +add ons: memoryfox and unload tab

results for me:

the constant flash crashes are there again, almost twice per hour, and ocassionally ffox crashes too, not so much but yes, it still happens. slowdowns are not so noticieable. but the flash crashing problem is there.

Thanks friends.

DonGateley 1 solutions 28 answers

Dobbs, I think it is time to suspect your add ons. I'm at 19.02 with Flash 11.6 r602, memory fox and unload tab without experiencing any issues at all. If you have a lot of add ons try a binary search to speed it up. Disable half of them and see if the problem goes away. If it does continue halving those you disabled. If not re-enable and start halving what you didn't disable. That will narrow it down fairly quick.

Question owner

Hi DonGateley,

yes, i have been trying disabling one by one, but i cant get to know wich one gives the problem...

im still with FFox crashes... i wish i could use Flash 10 really....

the addons i use are:

-chat undetected -custom tab width -menu editor -session manager -screen grab -stylish -try again -unload tab -memory fox -youtube video replay

maybe any of those is know to give problems?


DonGateley 1 solutions 28 answers

Try Session Manager. It is a beast and if it gets out of whack it can cause problems. Delete all the backup sessions other than the couple most recent and then remove all the deleted sessions.

If that doesn't help, uninstall/reinstall it. The options and sessions are retained. If you are still hamstrung about the only thing left is systematically disabling all addons until you get a hit.

These guys could do so much more at providing forensics for these problems but they are having too much fun developing.

Question owner

Thanks for the help.

I will try what you say and post an UPDATE soon.

Thanks a lot for the info.

Thats a big reality, many add ons are so greatly useful but yeah... they can give problems and is really hard to know wich one and solve those issues...

Question owner


Heres an UPDATE:

As always DonGateley, you were right.

WITHOUT SESSION MANAGER ADDON: -flash 11.6 still have slowdowns... and crashes but not so frequently. -ffox doesnt crash.

My problem is that Session Manager is vital for me as i use many tabs open and when i get a crash i need something like that to re-open fast where i was before...

But yes, the core of the problem seems to be: LATEST FLASH SESSION MANAGER ADD ON


DonGateley 1 solutions 28 answers

Yes, Session Manager is absolutely vital to me as well. It's the primary reason I remain wedded to FF. I have a rather massive topical set of unloaded auto-save windows which keeps my active window load low.

Did you take the steps with Session Manager that I recommended? As I've said probably too often, all is currently well on my installation which includes it.

FF does occasionally go unresponsive for short periods but not often enough or long enough to be much of a nuisance.

Question owner

Yes, i took those steps but saw no difference.

Firefox crashed two times per hour or more.


the real difference came when i disable the SM addon...

no more crashes of FFOX...

Flash is still a problem, but it seems the main engine of ffox is more stable now...

are there any alternative to SM? any other addon?

i dont think so but anyway...

thanks again... ;)

DonGateley 1 solutions 28 answers

No, there's nothing remotely as capable as Session Manager. On any browser. Why don't you go to the Session Manager feedback site and ask for help.


Morac can be pretty helpful and is very responsive to polite questions. Other than that, 'fraid I'm fresh out of ideas.

You've reminded me to send him another donation.

Modified by DonGateley

gibbygibson 0 solutions 2 answers

Another thing that works if you want to use all current versions is to go to Advanced tab in Firefox, then choose Update. Check "never check for updates" and uncheck "automatically update search engines." Kind of a hassle, but at least it is something you can do when trying to run flash player. It works for me...

Question owner

DonGateley: thanks as always for ur kind reply, yes, i will try to post there explaining my problem, now is know is some sort of combination of ffox, flash and smanager.

gibbygibson: thank you, yes, i tried that when using Flash 10. To be sincere i would like to keep using flash 10 as all was working smooth there, but i know also that the security concerns of using it are high, so, is a risk.

Actually im using ffox + latest flash + all the addons LESS smanager, i miss it like hell! but well... this way i only have flash crashes now and then and no ffox main engine crashes... so, well. seems the only way for me by now....

thanks friends!

gibbygibson 0 solutions 2 answers

Best of luck with it. Sometimes it just comes down to choosing the lesser evils... :-)

Question owner


Well, after days of using FFOX 19.0.2 with memfox and unloadtab activated and session manager deactivated i must say that FLASH keeps giving me problems... there are slowdowns and choppy youtube playback... the only way for me is going to the taskbar and closing the Flash pluging, and then reload... it works fine for a while and then again.... slowiness and choppiness... oh well....

Crashes of ffox have not gone away, they are VERY LESS frequent.. but they still ocurr... but still the main problem is flash... seems to be DRAGGING the whole system sometimes...

Any other suggestion to try?

THANKS friends!

amasters 0 solutions 1 answers

I have edited this post. I had earlier thought I had found the cause of the problem. (I thought it was a plugin called "WPI Detector".)

Disabling the plugin appeared to fix the problem. Everything worked great for a prolonged period, and then got jacked up again. My cursor begins fluttering between an arrow and the animated circular icon that indicates the something is being processed. At the same time this is happening, the Firefox icon in the task bar begins fluttering. This is very annoying. It even did this in Firefox safe mode, which eliminates plugins as the culprit.

Modified by amasters