Rights defenders say are cracking down on activists over a mysterious call for on November 11 -- when world leaders will convene at the .
The measures, which have included random phone searches and summons for interrogation, began in October, according to prominent opposition lawyer Khaled Ali.
"Almost every day, state security is arresting and interrogating people about the call to protest on November 11," the former presidential candidate wrote on Facebook Friday, after hashtags began appearing calling for the mass demonstrations.
The online "movement" is amorphous and comes despite protests having effectively been banned for years. While its origins are unknown, the calls have been backed by several opposition figures and media based abroad.
They moreover coincide with the United Nations climate summit, which has drawn further scrutiny of Egypt's rights record, as well as calls to guarantee the right to freedom of assembly.
The proposed date of the demonstration is the same as the expected arrival of US President Joe Biden for COP27, which Egypt is hosting in the remote resort town of Sharm el-Sheikh.
The online calls also come as the value of the local currency is at an all-time low, having shed over 50 percent of its value this year, while annual inflation is hovering above 15 percent.
The latest depreciation of the pound was a requirement for Egypt to clinch a $3 billion loan deal from the International Monetary Fund (IMF).
President Abdel Fattah al-Sisi has himself said that "anyone who makes less than 10,000 Egyptian pounds ($415) per month cannot live" in the country, where a third of the population scrapes by on less than 2,200 pounds a month.
With some 60,000 political prisoners already behind bars and a stranglehold on the independent press, a crackdown on dissent remains in place -- even as Sisi's administration gestures towards liberalisation.
Ahead of the main planned protest, there have been calls on Twitter for a "dress rehearsal".
Egyptians were urged to take to the streets last Friday after a football match between the country's two biggest clubs, Al Ahly and Zamalek.
In September 2019, it was also after such a match that rare protests calling for Sisi's removal took place in Tahrir Square, the epicentre of the 2011 uprising that toppled long-time autocrat Hosni Mubarak.
But as Friday came, cafes and restaurants around Tahrir and elsewhere had already closed their doors in response to police orders, some owners told AFP.
By the end of the match, plainclothes and uniformed officers were deployed around Tahrir, which was empty of any demonstrators.
Downtown Cairo has seen "passers-by arrested and their phones searched" for days, human rights lawyer Mahienour El-Massry tweeted.
"Why? Based on what law? And all this as they speak of a dialogue and a new republic where all opinions are welcome," Massry continued.
For six months, authorities have been preparing for a "national dialogue" that brings together political parties and opposition factions, at Sisi's behest.
But despite recent presidential pardons and the release of several high-profile political prisoners, the initiative has been met with scepticism.
The secretariat has already met a dozen times, but the dialogue has yet to start.
On Friday, Amnesty International reported that Turkey-based Egyptian journalist Hossam Elghamry had been arrested by Turkish security forces, "raising fears of deportation".
Elghamry, who has since been released, had earlier tweeted that Friday would be "a dress rehearsal for Egypt #after_the_match".
Local media in Egypt reported the news, calling Elghamry a member of the Muslim Brotherhood, which was outlawed and designated a terrorist organisation following the 2013 military ouster of late Islamist president Mohamed Morsi.
Calls for change seem also to be coming from those closer to power. On October 19, politician Mohamed Anwar al-Sadat, who has successfully negotiated for the release of political prisoners, published a letter.
To cap the president's great successes, the politician wrote, he should "not run for president in 2024, and be content with all the great achievements already made".