Former club chairman Stewart Gilmour took umbrage to comments made by Stubbs during a heated Twitter exchange with a St Mirren supporter following the 1-1 draw with Hamilton on Saturday, which condemned Saints to a place in the bottom six.
Stubbs took charge of the Buddies in June 2018 but was sacked after only three months and nine matches with the club languishing second bottom of the Premiership. He was replaced by Oran Kearney, who was succeeded by Jim Goodwin only 10 months later.
Goodwin took the Paisley club to the brink of a top six place at the weekend only to see it snatched away by a late equaliser from Hamilton, with St Johnstone claiming the spot by virtue of a late 1-0 win over Ross County.
Having narrowly avoided relegation in each of the past two seasons, Saints chief executive, Tony Fitzpatrick, raised eyebrows last summer when he claimed the club was targeting a top six finish this season, and his BBC interview was shared on Twitter ahead of the weekend fixtures.
Stubbs was tagged among the responses, with one fan tweeting: "Hopefully if we do it. There’s a bit of trolling for @alanstubbs_6."
This prompted Stubbs to respond after results confirmed that his former side had missed out on the top six. He replied: "Never mind eh,so close! But well done St Johnstone Top 6 and League Cup winners."
A further exchange ensued with the supporter directing offensive insults at the former Hibs boss, who then replied with laughing emojis, adding: "Might finish top six now playing the teams in the bottom 6!!"
This saw ex-St Mirren owner Gilmour, who sold the club back in 2016 after 20 years at the helm, join the conversation, messaging to Stubbs: "This is the most pathetic tweet, in particular for a guy always being punted for a job. The people who keep placing your name in there must be embarrassed. Hope every chairman sees this and would not touch you with a barge pole."
Stubbs hit back: "Good that your not one any more then Stewart! We have something in common then, we have not done anything since we left the club then!! Mine by choice though!"
The fiery exchange continued with Gilmour replying: "Just had Dinner, then pick up this, absolutely incredible, sorry to inform you in my case it is retirement, have done my bit!!! Relaxing with a few games of golf, international travel, emptying my bucket list!! Certainly no regrets, no axes, I sympathise with your trauma."
The public spat concluded with Stubbs replying: "Me too, hopefully see you on your travels and have a drink, golf! No trauma whatsoever believe me!!"
Stubbs has previously questioned the nature of his departure from St Mirren, describing his sacking as "very harsh", adding: "I won one in four [league games] and among those four we played Rangers at Ibrox, Hearts at Tynecastle.
He guided Hibs to Scottish Cup glory for the first time in 114 years in 2016 then had a short-lived spell in charge of English Championship side Rotherham United.