This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Hierdie gesprek is in die argief. Vra asseblief 'n nuwe vraag as jy hulp nodig het.

Text search typing very slow

  • 7 antwoorde
  • 1 het hierdie probleem
  • 1 view
  • Laaste antwoord deur John99

more options

Hi, when I open a large text file in Firefox (log file) and need to search for string using Ctrl + F, the typing of the string is very slow. It looks, that searching of each character takes significantly longer then in previous versions of Firefox. Unfortunately I can not remember, which Firefox version update started to experience this. It takes so long, that after typing each character you have to wait few seconds, until the search engine goes thru entire text and find first match. Only then second character is being searched and matching result given.

In previous versions the searching of text string within the text file was pretty fast. Comparable to searching in any text editor (Notepad++ etc.). Now it is not even usable, if the text file is really large (more then 1MB).

I have impression, that previously the search engine started to search after typing entire string in the search field and perhaps pressing enter. Now it starts to search with each letter typed in the field, what makes it unusable slow.

I have tested on various Windows machines, using Windows 7, 8 and 10.

Hi, when I open a large text file in Firefox (log file) and need to search for string using Ctrl + F, the typing of the string is very slow. It looks, that searching of each character takes significantly longer then in previous versions of Firefox. Unfortunately I can not remember, which Firefox version update started to experience this. It takes so long, that after typing each character you have to wait few seconds, until the search engine goes thru entire text and find first match. Only then second character is being searched and matching result given. In previous versions the searching of text string within the text file was pretty fast. Comparable to searching in any text editor (Notepad++ etc.). Now it is not even usable, if the text file is really large (more then 1MB). I have impression, that previously the search engine started to search after typing entire string in the search field and perhaps pressing enter. Now it starts to search with each letter typed in the field, what makes it unusable slow. I have tested on various Windows machines, using Windows 7, 8 and 10.

All Replies (7)

more options

The slowness means the CPU is being overworked.

Why are you using Firefox instead of a text program?


Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac=Options)
key, and then starting Firefox. A small dialog should appear. Click Start In Safe Mode (not Refresh).

Is the problem still there?


https://support.mozilla.org/en-US/kb/websites-look-wrong-or-appear-differently

https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster

https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix

https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding

https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding

more options

I work in support. We have a log repository on the server, accessed via browser. It simply opens text file in browser window and provides me with a quick look into log. It doesn't matter, if the file is loading from network or if the file is already loaded. It is still slow and almost unresponsive, when searching strings.

I started Firefox in SafeMode. I could see slightly better performance, but it is still almost unusable.

I have just tested it with IE and the result is the same. It looks it has something to do with Windows, rather than browser itself. Or perhaps it is related to our log repository server. I have no outside link for such large text files (>1MB) other then our server to test.

more options

Have you compared what happens if you download the log file and then search it in Firefox. From your first post it sounds as if you have and find no difference.

I just tried loading a 1/2 MB plain text file & Firefox had no issues searching it in real time. Many search strings indicated over 100 matches but the matches kept up with my admittedly slow typing. I am using Windows at present. I did only test on a 1/2 MB file if necessary I could just copy and paste such chunks to concatenate into a much larger file, but from your second post it sounds like you are tending to rule out this issue being Firefox specific.

more options

John99 said

Have you compared what happens if you download the log file and then search it in Firefox. From your first post it sounds as if you have and find no difference. I just tried loading a 1/2 MB plain text file & Firefox had no issues searching it in real time. Many search strings indicated over 100 matches but the matches kept up with my admittedly slow typing. I am using Windows at present. I did only test on a 1/2 MB file if necessary I could just copy and paste such chunks to concatenate into a much larger file, but from your second post it sounds like you are tending to rule out this issue being Firefox specific.

The searching itself can be fast, but the typing is the problem. First 1-3 letters appear quickly, but each next letter takes ages to appear (it seems it is searching the text for the 3rd...4th...letter, what takes terribly slow). And yes, it happens with both Firefox and IE.

The only workaround for me is to download text file to local HDD and open it in Notepad or any other text viewer/editor. It is annoying compared what Firefox was giving to me in that matter couple versions ago.

more options

What is notable is your discovery IE & Firefox have the same issue. That almost certainly indicates it is a local or machine specific problem.

Do I understand you see a slow search in Firefox when that file is on the local hdd ? My test on a 1/2 MB text test file had no issues with searching for long words or multiple words. Are you able to try with a text file of about 1/2 MB on the hdd for comparison. What sort of size are your problem log files  ? I will create and test with a similar size file on my hdd. I have multiple versions of Firefox available which version worked I can compare that, although I suspect it may not make a difference . As a more realistic test if you wish to post a public test text file & give me the link I will test that.

If this is actually a regression between versions it would be fairly serious & probably be reported & fixed quickly.

more options

John99 said

What is notable is your discovery IE & Firefox have the same issue. That almost certainly indicates it is a local or machine specific problem. Do I understand you see a slow search in Firefox when that file is on the local hdd ? My test on a 1/2 MB text test file had no issues with searching for long words or multiple words. Are you able to try with a text file of about 1/2 MB on the hdd for comparison. What sort of size are your problem log files  ? I will create and test with a similar size file on my hdd. I have multiple versions of Firefox available which version worked I can compare that, although I suspect it may not make a difference . As a more realistic test if you wish to post a public test text file & give me the link I will test that. If this is actually a regression between versions it would be fairly serious & probably be reported & fixed quickly.

Hello, you are right. This must be machine specific. I have tried to copy that file (>2MB) to my home computer and all is working smoothly, while my work laptop (newer model and reinstalled to W10) is still searching slow. Even when I open the file from local HDD (file:///C:). I can not share the file, bcs. it contains sensitive client's info. However, it happens with any larger text file (about 2MB of size).

more options

Thanks for the reply, but it is no longer looking like a Firefox problem so there is not much I can do. It would be interesting to know in due course what the problem and solution is.