This is a great question and this topic is a constant battle for Human Resources! The thing to keep in mind is that while you are an employee of an organization you are an advocate for that organization. Employers take this approach when considering someone for employment. Recruiters will often steer clear of a candidate with inappropriate/offensive content because it could damage the company's name down the line. As mentioned previously, many employers will screen candidate's social media to get an understanding of if the candidate would be a good culture fit. Bottom line, don't post something unless you are comfortable discussing it with your colleagues or supervisor.
This is a very interesting question with a bunch of different potential answers. These days, most employers have policies that deal with employee's use of social media since so many of these sites also have business applications. It's a lot easier to deal with toxic users when they are already employed since most employees sign policies or handbooks agreeing to the company's policies and agreeing to certain online behaviour.
A number of employers will Google potential employees to see what their online activity is. While I can't speak for all employers, if something came to light that was toxic, negative, demeaning, offensive..... I would absolutely hesitate to employ that person. Today, they can be talking about their lunch experience but tomorrow, they can be ranting about your company or their boss or their management team. With so much of our brands dependent on social media, negative posts also affect our bottom lines.
What you do online does affect you - the internet is forever.
Not all employers will search out employees online before they hire so it really depends on the job and the company. I would suggest larger organizations with a recognized brand and lots of online engagement will likely be more diligent/ stringent when they hire.
Also, most companies do have a policy about how their employees can use Social Media while employed. There could also be post-hire ramifications if you were a toxic social media user.
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