Note 21 - Segment Reporting - Summary of Segment Reporting Information (Details) - USD ($)		3 Months Ended						6 Months Ended
		Jun. 30, 2021		Mar. 31, 2021	Jun. 30, 2020		Mar. 31, 2020	Jun. 30, 2021		Jun. 30, 2020		Dec. 31, 2020
Revenues		$ 14,551,000			$ 10,416,000			$ 22,947,000		$ 14,800,000
Cost of revenues		14,769,000			10,118,000			23,882,000		13,603,000
Total operating expenses		8,061,000			1,318,000			9,159,000		4,493,000
Depreciation and amortization expense included in total operating expenses		170,000			208,000					415,000
Operating (loss)/income		(8,279,000)			(1,020,000)			(10,094,000)		(3,296,000)
Change in fair value of warrant liabilities		4,322,000			22,000			6,829,000		68,000
Net (loss)/income		(3,646,000)		$ 687,000	(970,000)		$ (2,310,000)	(2,959,000)		(3,280,000)
Expenditure for long-term assets		221,000						1,381,000		302
Total assets		36,948,000						36,948,000				$ 20,667,000
Corporate, Non-Segment [Member]
Revenues		0			0			0		645,000
Cost of revenues		0			0			0		0
Total operating expenses		7,399,000	[1]		380,000	[2]		7,910,000	[3]	2,528,000	[4]
Depreciation and amortization expense included in total operating expenses		0			1,000			1,000		2,000
Operating (loss)/income		(7,399,000)			(380,000)			(7,910,000)		(1,883,000)
Change in fair value of warrant liabilities		4,322,000			22,000			6,829,000		68,000
Net (loss)/income		(3,061,000)			(311,000)			(970,000)		(1,830,000)
Expenditure for long-term assets		161,000						161,000		0
Total assets		45,422,000						45,422,000				27,766,000
Intersegment Eliminations [Member]
Revenues		0			0			0		0
Cost of revenues		0			0			0		0
Total operating expenses		0			0			0		0
Depreciation and amortization expense included in total operating expenses		0			0			0		0
Operating (loss)/income		0			0			0		0
Change in fair value of warrant liabilities		0			0			0		0
Net (loss)/income		0			0			0		0
Expenditure for long-term assets		0						0		0
Total assets		(28,987,000)						(28,987,000)				(23,024,000)
Internet Ad [Member] | Operating Segments [Member]
Revenues		14,293,000			9,912,000			22,560,000		13,148,000
Cost of revenues		14,394,000			9,743,000			23,132,000		12,853,000
Total operating expenses		207,000			930,000			590,000		1,952,000
Depreciation and amortization expense included in total operating expenses		95,000			206,000			130,000		412,000
Operating (loss)/income		(308,000)			(761,000)			(1,162,000)		(1,657,000)
Change in fair value of warrant liabilities		0			0			0		0
Net (loss)/income		(12,000)			(757,000)			(966,000)		(1,650,000)
Expenditure for long-term assets		60,000						1,220,000		0
Total assets		11,515,000						11,515,000				8,310,000
Ecommerce O2O Ad and Marketing Services [Member] | Operating Segments [Member]
Revenues		258,000			504,000			387,000		1,007,000
Cost of revenues		375,000			375,000			750,000		750,000
Total operating expenses		455,000			5,000			658,000		9,000
Depreciation and amortization expense included in total operating expenses		75,000			0			150,000		0
Operating (loss)/income		(572,000)			124,000			(1,021,000)		248,000
Change in fair value of warrant liabilities		0			0			0		0
Net (loss)/income		(572,000)			101,000			(1,021,000)		204,000
Expenditure for long-term assets		0						0		0
Total assets		4,588,000						4,588,000				3,206,000
Blockchain Technology [Member] | Operating Segments [Member]
Revenues		0			0			0		0
Cost of revenues		0			0			0		0
Total operating expenses		0			3,000			1,000		4,000
Depreciation and amortization expense included in total operating expenses		0			1,000			1,000		1,000
Operating (loss)/income		0			(3,000)			(1,000)		(4,000)
Change in fair value of warrant liabilities		0			0			0		0
Net (loss)/income		(1,000)			$ (3,000)			(2,000)		(4,000)
Expenditure for long-term assets		0						0		$ 302
Total assets		$ 4,410,000						4,410,000				$ 4,409,000
Corporate Segment [Member]
Revenues								22,947,000
Cost of revenues								23,882,000
Total operating expenses	[3]							9,159,000
Depreciation and amortization expense included in total operating expenses								282,000
Operating (loss)/income								(10,094,000)
Change in fair value of warrant liabilities								$ 6,829,000

[1] Including approximately US$6.76 million share-based compensation expenses.

[2] Including approximately US$0.07 million share-based compensation expenses.

[3] Including approximately US$6.86 million share-based compensation expenses.

[4] Including approximately US$1.99 million share-based compensation expenses.