User Agent: Mozilla/5.0 (Windows NT 5.1; rv:32.0) Gecko/20100101 Firefox/32.0 Build ID: 20140911151253 Steps to reproduce: First I have open mozilla site. I was testing an connection with about:preferences/Content/Colors switched to system colors. I turned Content Browser using ctrl+alt+shift+I. Then I found I need to disable the System Colors because I cannot see injected styles on web-page. I clicked on Tools/Options. Actual results: To open the Window it takes some time, few seconds. First I see white empty tab. When window content and controls are displayed then I click on Content icon/reference. I wait long time but I cannot see the page to be refreshed. Currently it seems I need to close the Debugger tool / Browser Content because I cannot change the colors so I would not see the color changes of injected styles. Expected results: 1) No delay, the window should be open immediately 2) Content must be refreshed and shown immediately 3) depends on bug 1288917 - work around is here simple: point 1 and 2 - add icon to Toggle colors settings because default colors option blocks displaying of webpage colors. I suggest to solve this blocking with an icon where I can define my prefered system color for "window" or "background". This way "default colors" are not needed and should not block the webpage colors.

Application, Security, Cinc also not accessible (at all)

Currently I have tested twice that the Firefox and Toolbox tool have been freezed definately when I opened the Options. Task manager - forced close of application needed.

Can you attach a screenshot? I am not sure I understand the issue yet, so a screenshot may help.

OK, first I send how Content - Colors options should work normally, when Content Toolbox is not connected. http://oi68.tinypic.com/mhd94k.jpg http://oi65.tinypic.com/opzfjr.jpg http://oi64.tinypic.com/doq7ma.jpg http://oi64.tinypic.com/33z429u.jpg http://oi63.tinypic.com/2i044qx.jpg http://oi67.tinypic.com/2qcj88j.jpg

ctrl+alt+shift+I Connect Content Toolbox http://oi63.tinypic.com/21lsx9t.jpg Open Content Scropt: http://oi66.tinypic.com/2ue2pzt.jpg Switch to Firefox webpage with injected script http://oi67.tinypic.com/2qcj88j.jpg Notice: At this point I try to set the option in the same way as described in the images, but I cannot find it to do any problems right now. Yet I try: Add breakpoint and debug: http://oi63.tinypic.com/102qdjn.jpg Finished debugging: http://oi67.tinypic.com/2qs0w1h.jpg I try options: http://oi63.tinypic.com/e625ok.jpg There was some small delay before the tab opened, but nothing strange. Currently I cannot reproduce the behaviour. I will try during today and next days and I will tell you more details when it will happen again.

Actually, I had set System colors when the issue arised. Today the reactions are much more better (faster) then yesterday. When I tried it again with System colors on, after I finished debugging, then I switch to FF, then I click on Tools and Options, and there is some delay to open the Options 3-4 seconds. To open the Content tab it took some time, but at this moment it took just few ms, about 250-300ms my guess. There is some process which makes this delay when I try to open the about:preferences page. At this moment I try to repeat, debugging (break at some point in listener), finished debugging, and then display Content. So far I wait 4s. Then I click Content tab and I wait much more ... This looks like it freezed now. This is what I see: http://oi63.tinypic.com/2ngbvht.jpg I try clicking once more on various tabs, and then the Content tab - content is loaded. But I click on the botton Colors and no Colors dialog is open. I repeat and then it is opened after some delay cca 1000ms.

(In reply to bugzilla12345678 from comment #6) > Actually, I had set System colors when the issue arised. Today the reactions > are much more better (faster) then yesterday. When I tried it again with > System colors on, after I finished debugging, then I switch to FF, then I > click on Tools and Options, and there is some delay to open the Options 3-4 > seconds. To open the Content tab it took some time, but at this moment it > took just few ms, about 250-300ms my guess. There is some process which > makes this delay when I try to open the about:preferences page. > > At this moment I try to repeat, debugging (break at some point in listener), > finished debugging, and then display Content. So far I wait 4s. Then I click > Content tab and I wait much more ... This looks like it freezed now. This is > what I see: > > http://oi63.tinypic.com/2ngbvht.jpg > > I try clicking once more on various tabs, and then the Content tab - content > is loaded. But I click on the botton Colors and no Colors dialog is open. I > repeat and then it is opened after some delay cca 1000ms. Okay, I'd like ask a few more questions to be sure I understand the description. What version of Firefox reproduces the issues? Is this the right sequence of steps? 1. Enable system colors 2. Use the Browser Toolbox and set a breakpoint 3. Go to Tools -> Options in Firefox 4. More debugging 5. Click on Content in the Firefox options tab: Firefox appears to freeze 7. Click on colors: no dialog appears When it appears to freeze, are you sure you aren't stopped at a breakpoint in the Browser Toolbox?

Currenly I am using FF 48.0b10. 1. Enable system colors 2. Use the Browser Toolbox and set a breakpoint 3. Debug and finish debugging (the Toolbox is still open) 4. Go to Tools -> Options in Firefox 5. Click on Content in the Firefox options tab: Firefox appears to freeze 7. Click on colors: no dialog appears You may need to repeat the steps 1-7 about 3 times or 4 times to notice that the delays are greater and that it finally freezes at step 5. For me (amateur) it looks like the Toolbox tool tries to analyse the about:preferences page (which is waste of resources). I would prefer, if the Toolbox could stay connected to the last/previous page I have open, so when I open about:preferences / Content it will not analyse it and no problems occur. Just my idea what I think it does.

Correction: You may need to repeat the steps 3-7 about 3 times or 4 times to notice that the delays are greater and that it finally freezes at step 5. In my case, I added breakpoint to even listener. When I clicked, it breaks in Content Script. Then I continue till it finishes. There is no breaken code in the moment when I open the Options/Preferences.

Right now, in version 48.0. It happened when I did forgot that the Toolbox is opened (yesterday). I did not do any debugging in this moment, and as far as I remember I did not do any debugging (yesterday) when the Toolbox was open. So I just came to my PC and needed to turn off system colors. First impression is, it freezed on Options page. Then I switched to window of FF32 and then I switched it back when I realized I should recheck FF version. And I see it is already opened so it is delay in miliseconds or seconds. Then I click on Content tab and I wait but not that long as when I opened the Options. Then I clicked on Colors and changed colors. The delay on the last dialogue window was small cca 250ms. But I feel it like waste of time. I repeat it and the same problem, takes about 4s and then small delays to open Content tab and Colors dialogue window.

Once again. After some time I spend in Toolbox and debuging. I needed to Display webpage colors. After I went to Options the Script freezed. I thought I will need to restart Firefox but after some time, bmaybe 20-30 seconds, window appeared askng me if I want to stop script preferences.xml or something like that.

Can you check Nightly Firefox (currently version 51) to see if the issue occurs there as well?

OK, I installed the current version and this is the result of "first glance" test. cca 10 seconds to open preferences. The delays to open Content tab and Colors are fine. Hoverver I will not do extensive testing in Toolbox of the Nightly because the dark scheme colors does not fit my needs. I see you use low contrast scheme so my eyes hurts when I use it. Also I am disapointed because when I started Nightly, I have started it to my default profile by incident which disabled adress line suggestions. I need to correct this back because this disables me very much.

I am not able to reproduce this issue with Windows 10. I don't have access to a machine with Windows XP to check there. We'll need more details on how to precisely to reproduce this issue to move forward. Since this only happens when the Browser Toolbox is used and seems to be a very specific configuration, marking P3.

FF 48 - update I have found that the problem with delays or freezing of the Options persists even when I close the Toolbox. This is well visible when I want to access Content tab, so no Content is displayed. I cannot do more do diagnose the problem, I have no tools for it. Maybe there are memory leaks, but without tools I cannot check.

IMPORTANT Today I have found new thing. This bug may not be related directly to Toolbox. I am running Firefox 48.0.1 in different profile than that one when I reported the bug. When I reported the bug I used different profile with Toolbox. Not this is different profile loaded and I did not use the toolbox here. I debugged a website using normal development tools, not for webextensions. I debugged a javascript function. I used Debugger, Console and Inspector. Now I needed to turn off system colors so I went to properties and FF has same symptoms: I cannot access the Content tab (while I write this post it still was not open). Before version 48 I used v 32 and I have never had such problems. Also sometimes I turn off and turn on system colors in the second profile which is not used for debugging and I had no problems with it. But when I used the normal debugger tools this happened. I often use Inspector here so I think problem is not in Inspector, but in Debugger. Also I have noticed - it was such feeling, that when the debugger is paused (not Toolbox) and I open new page, so the loading goes slower (I guess 2x slower). For me this is obstacle.