How to fix exim Could not complete sender verify

Check if you can reach a remote server

dig a gmail.com

If this timeouts then try over one of dns resolver directly

[~]# dig @8.8.8.8 a gmail.com

; <<>> DiG 9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.2 <<>> @8.8.8.8 a gmail.com
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached

Timeout means DNS resolver is dead

[~]# cat /etc/resolv.conf
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How to fix “Sorry, you are not allowed to access this page.”

Using WP-CLI

If you see an empty ROLES then it is

wp user list
+----+------------+--------------+--------------------------------+---------------------+---------------+
| ID | user_login | display_name | user_email            | user_registered                | roles |
+----+------------+--------------+--------------------------------+---------------------+---------------+
| 1  | admin1     | admin1           | [email protected] | 2018-06-19 17:00:02 |         |
+----+------------+--------------+--------------------------------+---------------------+---------------+

So add admin right for this user:

wp user set-role 1 administrator

Check it, should be good now:

wp user list
+----+------------+--------------+--------------------------------+---------------------+---------------+
| ID | user_login | display_name | user_email            | user_registered                | roles |
+----+------------+--------------+--------------------------------+---------------------+---------------+
| 1  | admin1     | admin1           | [email protected]
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How to create a file of specific size using Linux command line

Reduce size using truncate command

Run for a second:

yes "some text" > testfile.txt

Reduce size using truncate:

truncate -s 50M testfile.txt

Create 50M file using fallocate command

fallocate -l 52428800 testfile.txt

To be more exact using inline arithmetic:

fallocate -l $((50*1024*1024)) testfile.txt
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How to change firefox default tab size and fix wonky tab behavior

Under your profile folder create a chrome/ folder

cd /home/`whoami`/.mozilla/firefox/*default*
mkdir chrome
cd chrome

Create userChrome.css file

touch userChrome.css

Update userChrome.css with the following lines:

@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);
.tabbrowser-tab:not([pinned]) {
max-width: 80px !important;
}
.tabbrowser-tab:not([pinned]):not([fadein]) {
max-width: 0.1px !important;
}

 

Restart firefox and enjoy

Source:
https://www.askvg.com/how-to-customize-and-change-width-or-length-of-tabs-in-mozilla-firefox/Read the rest