FIREFOX - performance improvement by cleaning up sqlite database

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LINUX COMMAND:  cd /home/luser/.mozilla/firefox/PROFILE-NAME.default ; sqlite3 places.sqlite "vacuum;"
    (you may need to install sqlite3, see details below)
    NOTE:  most Linux distros will have this same path, however the install of the tool will vary

MAC COMMAND:     cd ~/Library/Application\ Support/Firefox/Profiles/*.default/ ; sqlite3 places.sqlite "vacuum;"
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LINUX PROCESS:   


1) open a terminal window (Konsole)
2) QUIT firefox; verify it's not running
3) cd to the firefox profile directory for your account
4) execute the command to vacuum 
5) restart firefox and enjoy

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-> cd /home/luser/.mozilla/firefox/PROFILE-NAME.default 
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    you can cd to this path with a shell shortcut:   
    cd ~/.mozilla/firefox  and then your unique profile name, 
        or type *.default in the path 
    cd ~/.mozilla/firefox/*.default 
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check to make sure you are there:
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-> pwd
/home/luser/.mozilla/firefox/PROFILE-NAME.default
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-> ls places.*
rw-r--r--  1 luser luser 36700160 Aug  2 10:26 places.sqlite
-rw-r--r--  1 luser luser    32768 Dec 13  2018 places.sqlite-shm
-rw-r--r--  1 luser luser  4096000 Aug  2 10:58 places.sqlite-wal
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MAKE SURE FIREFOX is not running

--> ps -ef | grep -i firefox
luser      9424  8008  0 11:04 pts/1    00:00:00 grep -i firefox
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clean the database - the tool may not be installed on your distro, YMMV:
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--> sqlite3 places.sqlite "vacuum;"

Command 'sqlite3' not found, but can be installed with:

sudo apt install sqlite3

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luser@mint-linux [/home/luser/.mozilla/firefox/PROFILE-NAME.default]
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--> sudo apt install sqlite3
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following package was automatically installed and is no longer required:
  libllvm7
Use 'sudo apt autoremove' to remove it.
Suggested packages:
  sqlite3-doc
The following NEW packages will be installed:
  sqlite3
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 753 kB of archives.
After this operation, 2,481 kB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 sqlite3 amd64 3.22.0-1ubuntu0.1 [753 kB]
Fetched 753 kB in 1s (629 kB/s)  
Selecting previously unselected package sqlite3.
(Reading database ... 268907 files and directories currently installed.)
Preparing to unpack .../sqlite3_3.22.0-1ubuntu0.1_amd64.deb ...
Unpacking sqlite3 (3.22.0-1ubuntu0.1) ...
Setting up sqlite3 (3.22.0-1ubuntu0.1) ...
Processing triggers for man-db (2.8.3-2ubuntu0.1) ...

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luser@mint-linux [/home/luser/.mozilla/firefox/PROFILE-NAME.default]
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--> sqlite3 places.sqlite "vacuum;"

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luser@mint-linux [/home/luser/.mozilla/firefox/PROFILE-NAME.default]
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--> ll places.*
-rw-r--r-- 1 luser luser 31555584 Aug  2 11:06 places.sqlite