The EU and Ukraine on Monday formally opened the first stage of accession negotiations with a view to Kyiv one day joining the 28-member bloc.   Russia's full-scale invasion of Ukraine in 2022 turbocharged an idea that at one point was contentious among the country's electorate. For the past two years, the process had been on hold. That's because starting it requires unanimous approval from existing EU governments, and Hungary's former Prime Minister Viktor Orban was blocking the move.  The