Selena Gomez All Smiles on 'Murders' Set Despite Drama with Kylie & Hailey

The Internet thinks Selena Gomez has been in a 'Mean Girls' tiff with Hailey Bieber and Kylie Jenner -- causing her to temporarily shut down her social media ... but it doesn't seem to have affected her mood in real life ... a really good one, it would appear.

The actress/singer was all smiles Tuesday while on the set for her hit Hulu show 'Only Murders in the Building' -- where she was seen coming out of her trailer in Manhattan with adoring fans on hand who were dying for selfies ... something SG was happy to oblige.

She looks pretty radiant here, and that's significant ... because for the past 4-5 days or so, she and her ex-BF's now-wife (Hailey) appear to have been trading barbs online -- with none other than Kylie getting in on it, who appears to be on Hailey's side in a war of pettiness.

Here's the deal ... Selena posted a goofy video last week  showing off her eyebrows, where she said she'd over-laminated, this in an attempt to praise Bella Hadid ... whom she was sorta over-gushing about. Kylie appeared to have responded shortly thereafter ... with this.

KJ threw up a photo of her face -- with a caption reading, "this was an accident???" next to her eyebrows, which many took as a shot at Selena in, perhaps, being attention-seeking.

After that, Kylie posted yet another photo ... this time showing a screengrab of a FT call she was having with Hailey -- and both of them focusing the frame on their eyebrows ... again being perceived as a shot at Selena, only this time with Hailey directly getting in the mix.

The Internet was having a field day -- with TikTokers making tons of analysis videos breaking down the purported feud -- and Kylie finally responded ... saying it was BS, to which Selena also responded in agreement. So, issue resolved ... right??? WRONG! SG wasn't done yet.

It seems Selena had a bit more to say about Hailey in particular ... commenting on an old, resurfaced clip of Hailey making a gagging reaction at the mention of Taylor Swift (Selena's BFF) and Selena responding, "So sorry, my best friend is and continues to be one of the best in the game." On the surface, it sounds like she wanted the final word on it all.

Of course, Selena responding just fueled the speculation about bad blood -- a la Justin Bieber and their messy history, etc. -- at which point Selena said she was hitting pause.

Selena took to TikTok in the past couple days to say she was deactivating her social accounts for a bit, adding that she was "too old" for this ... but not really explaining in detail what "this" was. It doesn't take a rocket scientist though -- either she's actually tired of HB/KJ's antics ... and/or the Internet fanning the flames of a possible beef between them.