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how can i change the number of jumped lines when scrolling?

  • 7 replies
  • 24 have this problem
  • 7 views
  • Last reply by cor-el

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  1. 1 when i scroll through i.e. an article by using the scroll wheel on my mouse, the text jumps up or down by five lines
  2. 2 when i go up or down using PgUp or PgDn the page jumps by more than its own length. i then have to scroll back to see the skipped lines

how can i adjust the number of skipped lines in both cases? tools>options doesn't let me do it myself?!

# 1 when i scroll through i.e. an article by using the scroll wheel on my mouse, the text jumps up or down by five lines # 2 when i go up or down using PgUp or PgDn the page jumps by more than its own length. i then have to scroll back to see the skipped lines how can i adjust the number of skipped lines in both cases? tools>options doesn't let me do it myself?!

All Replies (7)

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For the first part of your question concerning scrolling with the mouse. By default Firefox will uses system settings for deciding how many lines to scroll when using the mouse wheel, but you can change it by modifying a couple of hidden preferences.

  1. Type about:config into the location bar and press enter
  2. Accept the warning message that appears and a list of preferences will appear
  3. In the filter box type numlines
  4. Double-click on the preference mousewheel.withnokey.sysnumlines to change its value to false
  5. Double-click on the preference mousewheel.withnokey.numlines and change it to the number of lines you want to scroll
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You can press the Alt key while using the scroll wheel to scroll one line.

mousewheel.withaltkey.action = 0 
mousewheel.withaltkey.numlines = 1
mousewheel.withaltkey.sysnumlines = false
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hi tony, this really did the trick. i never knew there was a thing like about:config. so it both works and taught me something. thanks.

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sorry cor-el, next time hopefully. of course it works, but i prefer working with just one hand if possible. thanks anyhow.

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You're welcome

You can or source use the Alt setting to move faster (e.g. 3 lines) and leave the default withnokey at 1 line. Then you can press Alt if you want to move faster.

By the way: prefs like this are a good candidate to place in user.js. Then you won't forget them and you can quickly initiate a new profile if needed. Be aware that you can not change prefs that are set via user.js permanently via about:config because user.js is read on every start.

Modified by cor-el

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OK, we tried this ... in fact, a couple of times, after the first time had it jumping 6 lines yet [huge default they have!] after doing the suggested.

SOOO, next question ... does this only work/register after the browser is closed down/reopened, or is there something else wrong?

Thank you!

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Some prefs are only read on startup and cached to improve performance. If those prefs need that then you will have to do that. You can check if opening a new window works as well and then close the other window.